Gross Amount of Recognized | Gross Amount of Cash Collateral | Net Amount Presented on Balance Sheet | ||||||||||||||||||
Assets | Liabilities | Offset | Assets | Liabilities | ||||||||||||||||
Fuel derivatives | ||||||||||||||||||||
As of December 31, 2017 | $ | — | $ | — | $ | — | $ | — | $ | — | ||||||||||
As of December 31, 2016 | $ | 22 | $ | — | $ | — | $ | 22 | $ | — |
December 31, 2017 | December 31, 2016 | |||||||||||||||
Carrying Value | Estimated Fair Value | Carrying Value | Estimated Fair Value | |||||||||||||
Public Debt | ||||||||||||||||
Fixed rate special facility bonds, due through 2036 | 42 | 46 | 42 | 45 | ||||||||||||
Non-Public Debt | ||||||||||||||||
Fixed rate enhanced equipment notes, due through 2023 | 169 | 178 | 188 | 197 | ||||||||||||
Floating rate equipment notes, due through 2025 | 152 | 159 | 171 | 179 | ||||||||||||
Fixed rate equipment notes, due through 2026 | 712 | 771 | 843 | 915 | ||||||||||||
Total(1) | $ | 1,075 | $ | 1,154 | $ | 1,244 | $ | 1,336 |
Aircraft Fuel Derivatives(1) | Interest Rate Swaps(2) | Total | ||||||||||
Balance of accumulated (losses), at December 31, 2014 | (63 | ) | — | (63 | ) | |||||||
Reclassifications into earnings (net of $49 of taxes) | 77 | 1 | 78 | |||||||||
Change in fair value (net of $(11) of taxes) | (18 | ) | — | (18 | ) | |||||||
Balance of accumulated income (losses), at December 31, 2015 | (4 | ) | 1 | (3 | ) | |||||||
Reclassifications into earnings (net of $(4) of taxes) | (5 | ) | (1 | ) | (6 | ) | ||||||
Change in fair value (net of $12 of taxes) | 22 | — | 22 | |||||||||
Balance of accumulated income, at December 31, 2016 | $ | 13 | $ | — | $ | 13 | ||||||
Reclassifications into earnings (net of $(6) of taxes) | (9 | ) | — | (9 | ) | |||||||
Change in fair value (net of $(2) of taxes) | (4 | ) | — | (4 | ) | |||||||
Balance of accumulated income, at December 31, 2017 | — | — | — | |||||||||
(1) Reclassified to aircraft fuel expense | ||||||||||||
(2) Reclassified to interest expense |
2017 | 2016 | |||||||||||||
Secured Debt | ||||||||||||||
Floating rate equipment notes, due through 2025(1) | $ | 153 | 4.7 | % | $ | 173 | 4.2 | % | ||||||
Fixed rate enhanced equipment notes, due through 2023(2) | 171 | 4.5 | % | 189 | 4.5 | % | ||||||||
Fixed rate equipment notes, due through 2026 | 716 | 5.4 | % | 850 | 5.5 | % | ||||||||
Fixed rate specialty bonds, due through 2036(3) | 43 | 4.9 | % | 43 | 4.9 | % | ||||||||
Capital Leases(4) | 124 | 4.5 | % | 140 | 4.3 | % | ||||||||
Total debt and capital lease obligations | 1,207 | 1,395 | ||||||||||||
Less: Current maturities | (196 | ) | (189 | ) | ||||||||||
Less: Debt acquisition cost | (8 | ) | (11 | ) | ||||||||||
Long-term debt and capital lease obligations | $ | 1,003 | $ | 1,195 |
Year | Maturities | |||
2018 | $ | 194 | ||
2019 | 215 | |||
2020 | 179 | |||
2021 | 164 | |||
2022 | 142 | |||
Thereafter | 305 |
December 31, 2017 | December 31, 2016 | |||||||||||||||
Carrying Value | Estimated Fair Value | Carrying Value | Estimated Fair Value | |||||||||||||
Public Debt | ||||||||||||||||
Fixed rate special facility bonds, due through 2036 | 42 | 46 | 42 | 45 | ||||||||||||
Non-Public Debt | ||||||||||||||||
Fixed rate enhanced equipment notes, due through 2023 | 169 | 178 | 188 | 197 | ||||||||||||
Floating rate equipment notes, due through 2025 | 152 | 159 | 171 | 179 | ||||||||||||
Fixed rate equipment notes, due through 2026 | 712 | 771 | 843 | 915 | ||||||||||||
Total(1) | $ | 1,075 | $ | 1,154 | $ | 1,244 | $ | 1,336 |
As of December 31, | ||||||||
2017 | 2016 | |||||||
Fuel derivatives | ||||||||
Asset fair value recorded in prepaid expense and other(1) | $ | — | $ | 22 | ||||
Longest remaining term (months) | — | 12 | ||||||
Hedged volume (barrels, in thousands) | — | 1,920 | ||||||
Estimated amount of existing (gains) expected to be reclassified into earnings in the next 12 months | — | (22 | ) |
2017 | 2016 | 2015 | ||||||||||
Fuel derivatives | ||||||||||||
Hedge effectiveness (gains) losses recognized in aircraft fuel expense | $ | (15 | ) | $ | (9 | ) | $ | 126 | ||||
(Gains) losses on derivatives not qualifying for hedge accounting recognized in other expense | — | — | 1 | |||||||||
Hedge (gains) losses on derivatives recognized in comprehensive income | 6 | (34 | ) | 29 | ||||||||
Percentage of actual consumption economically hedged | 10 | % | 12 | % | 17 | % |
(1) | Gross asset of each contract prior to consideration of offsetting positions with each counterparty and prior to impact of collateral paid. |
Gross Amount of Recognized | Gross Amount of Cash Collateral | Net Amount Presented on Balance Sheet | ||||||||||||||||||
Assets | Liabilities | Offset | Assets | Liabilities | ||||||||||||||||
Fuel derivatives | ||||||||||||||||||||
As of December 31, 2017 | $ | — | $ | — | $ | — | $ | — | $ | — | ||||||||||
As of December 31, 2016 | $ | 22 | $ | — | $ | — | $ | 22 | $ | — |
Shares | Weighted Average Grant Date Fair Value | |||||
Nonvested at beginning of year | 1.8 | $16.77 | ||||
Granted | 0.9 | 19.76 | ||||
Vested | (1.0 | ) | 14.04 | |||
Forfeited | (0.1 | ) | 19.69 | |||
Nonvested at end of year | 1.6 | $20.14 |
Shares | Weighted Average Grant Date Fair Value | |||||
Outstanding at beginning of year | 0.4 | $10.90 | ||||
Exercised | (0.4 | ) | 10.90 | |||
Outstanding at end of year | — | — | ||||
Vested at end of year | — | — |
2017 | 2016 | 2015 | ||||||||||
Numerator: | ||||||||||||
Net income | $ | 1,147 | $ | 759 | $ | 677 | ||||||
Effect of dilutive securities: | ||||||||||||
Interest on convertible debt, net of income taxes and profit sharing | — | 2 | 4 | |||||||||
Net income applicable to common stockholders after assumed conversions for diluted earnings per share | $ | 1,147 | $ | 761 | $ | 681 | ||||||
Denominator: | ||||||||||||
Weighted average shares outstanding for basic earnings per share | 328.7 | 326.5 | 315.1 | |||||||||
Effect of dilutive securities: | ||||||||||||
Employee stock options and restricted stock units | 1.7 | 2.1 | 2.8 | |||||||||
Convertible debt | — | 13.6 | 26.9 | |||||||||
Adjusted weighted average shares outstanding and assumed conversions for diluted earnings per share | 330.4 | 342.2 | 344.8 |
As of December 31, 2017 | ||||||||||||||||
Level 1 | Level 2 | Level 3 | Total | |||||||||||||
Cash equivalents | $ | 173 | $ | — | $ | — | $ | 173 | ||||||||
Available-for-sale investment securities | — | 136 | — | 136 |
As of December 31, 2016 | ||||||||||||||||
Level 1 | Level 2 | Level 3 | Total | |||||||||||||
Cash equivalents | $ | 313 | $ | — | $ | — | $ | 313 | ||||||||
Available-for-sale investment securities | 115 | 220 | — | 335 | ||||||||||||
Aircraft fuel derivatives | — | 22 | — | 22 |
2017 | 2016 | 2015 | ||||||||||
Deferred: | ||||||||||||
Federal | $ | (361 | ) | $ | 245 | $ | 351 | |||||
State | 25 | 25 | 26 | |||||||||
Foreign | 23 | — | — | |||||||||
Deferred income tax (benefit) expense | (313 | ) | 270 | 377 | ||||||||
Current: | ||||||||||||
Federal | 94 | 129 | 20 | |||||||||
State | 18 | 26 | 16 | |||||||||
Foreign | (25 | ) | 32 | 7 | ||||||||
Current income tax expense | 87 | 187 | 43 | |||||||||
Total income tax (benefit) expense | $ | (226 | ) | $ | 457 | $ | 420 |
2017 | 2016 | 2015 | ||||||||||
Income tax expense at statutory rate | $ | 322 | $ | 425 | $ | 384 | ||||||
State income tax, net of federal benefit | 28 | 34 | 28 | |||||||||
Adjustment of net deferred tax liability from enacted tax rate change | (570 | ) | — | — | ||||||||
Other, net | (6 | ) | (2 | ) | 8 | |||||||
Total income tax (benefit) expense | $ | (226 | ) | $ | 457 | $ | 420 |
2017 | 2016 | |||||||
Deferred tax assets: | ||||||||
Deferred revenue/gains | 95 | 121 | ||||||
Terminal 5 lease | 45 | 38 | ||||||
Employee benefits | 32 | 41 | ||||||
Foreign tax credit | 23 | — | ||||||
Rent expense | 22 | 34 | ||||||
Other | 6 | 8 | ||||||
Deferred tax assets, net | 223 | 242 | ||||||
Deferred tax liabilities: | ||||||||
Accelerated depreciation | (1,256 | ) | (1,596 | ) | ||||
Deferred tax liabilities | (1,256 | ) | (1,596 | ) | ||||
Net deferred tax liability | $ | (1,033 | ) | $ | (1,354 | ) |
2017 | 2016 | 2015 | ||||||||||
Unrecognized tax benefits at January 1, | $ | 26 | $ | 21 | $ | 16 | ||||||
Increases for tax positions taken during a prior period | 2 | 10 | — | |||||||||
Increases for tax positions taken during the period | 6 | 5 | 6 | |||||||||
Decreases for tax positions taken during a prior period | (3 | ) | (4 | ) | (1 | ) | ||||||
Decreases for settlement with tax authorities during the period | — | (6 | ) | — | ||||||||
Unrecognized tax benefits December 31, | $ | 31 | $ | 26 | $ | 21 |
Aircraft | Other | Total | ||||||||||
2018 | $ | 71 | $ | 99 | $ | 170 | ||||||
2019 | 59 | 91 | 150 | |||||||||
2020 | 57 | 74 | 131 | |||||||||
2021 | 51 | 66 | 117 | |||||||||
2022 | 45 | 62 | 107 | |||||||||
Thereafter | 139 | 378 | 517 | |||||||||
Total minimum operating lease payments | $ | 422 | $ | 770 | $ | 1,192 |
2017 | 2016 | |||||||
Available-for-sale securities | ||||||||
Time deposits | $ | 130 | $ | 160 | ||||
Debt Securities | 6 | — | ||||||
Treasury bills | — | 115 | ||||||
Commercial paper | — | 60 | ||||||
Total available-for-sale securities | 136 | 335 | ||||||
Held-to-maturity securities | ||||||||
Treasury notes | 220 | 283 | ||||||
Corporate bonds | 36 | 10 | ||||||
Total held-to-maturity securities | 256 | 293 | ||||||
TOTAL INVESTMENT SECURITIES | $ | 392 | $ | 628 |
2017 | 2016 | |||||||
Available-for-sale securities | ||||||||
Time deposits | $ | 130 | $ | 160 | ||||
Debt Securities | 6 | — | ||||||
Treasury bills | — | 115 | ||||||
Commercial paper | — | 60 | ||||||
Total available-for-sale securities | 136 | 335 | ||||||
Held-to-maturity securities | ||||||||
Treasury notes | 220 | 283 | ||||||
Corporate bonds | 36 | 10 | ||||||
Total held-to-maturity securities | 256 | 293 | ||||||
TOTAL INVESTMENT SECURITIES | $ | 392 | $ | 628 |
Property and Equipment Type | Estimated Useful Life | Residual Value | |||
Aircraft | 25 years | 20 | % | ||
In-flight entertainment systems | 5-10 years | 0 | % | ||
Aircraft parts | Fleet life | 10 | % | ||
Flight equipment leasehold improvements | Lower of lease term or economic life | 0 | % | ||
Ground property and equipment | 2-10 years | 0 | % | ||
Leasehold improvements—other | Lower of lease term or economic life | 0 | % | ||
Buildings on leased land | Lease term | 0 | % |
Property and Equipment Type | Estimated Useful Life | Residual Value | |||
Aircraft | 25 years | 20 | % | ||
In-flight entertainment systems | 5-10 years | 0 | % | ||
Aircraft parts | Fleet life | 10 | % | ||
Flight equipment leasehold improvements | Lower of lease term or economic life | 0 | % | ||
Ground property and equipment | 2-10 years | 0 | % | ||
Leasehold improvements—other | Lower of lease term or economic life | 0 | % | ||
Buildings on leased land | Lease term | 0 | % |
First Quarter | Second Quarter | Third Quarter | Fourth Quarter | |||||||||||||
2017 | ||||||||||||||||
Operating revenues | $ | 1,604 | $ | 1,842 | $ | 1,813 | $ | 1,756 | ||||||||
Operating income | 147 | 354 | 310 | 189 | ||||||||||||
Net income(1) | 85 | 211 | 179 | 672 | ||||||||||||
Basic earnings per share | $ | 0.25 | $ | 0.64 | $ | 0.55 | $ | 2.09 | ||||||||
Diluted earnings per share(1) | $ | 0.25 | $ | 0.64 | $ | 0.55 | $ | 2.08 | ||||||||
2016 | ||||||||||||||||
Operating revenues | $ | 1,616 | $ | 1,643 | $ | 1,732 | $ | 1,641 | ||||||||
Operating income | 349 | 313 | 354 | 296 | ||||||||||||
Net income | 207 | 181 | 199 | 172 | ||||||||||||
Basic earnings per share | $ | 0.64 | $ | 0.56 | $ | 0.61 | $ | 0.51 | ||||||||
Diluted earnings per share | $ | 0.61 | $ | 0.53 | $ | 0.58 | $ | 0.50 |
Aircraft Fuel Derivatives(1) | Interest Rate Swaps(2) | Total | ||||||||||
Balance of accumulated (losses), at December 31, 2014 | (63 | ) | — | (63 | ) | |||||||
Reclassifications into earnings (net of $49 of taxes) | 77 | 1 | 78 | |||||||||
Change in fair value (net of $(11) of taxes) | (18 | ) | — | (18 | ) | |||||||
Balance of accumulated income (losses), at December 31, 2015 | (4 | ) | 1 | (3 | ) | |||||||
Reclassifications into earnings (net of $(4) of taxes) | (5 | ) | (1 | ) | (6 | ) | ||||||
Change in fair value (net of $12 of taxes) | 22 | — | 22 | |||||||||
Balance of accumulated income, at December 31, 2016 | $ | 13 | $ | — | $ | 13 | ||||||
Reclassifications into earnings (net of $(6) of taxes) | (9 | ) | — | (9 | ) | |||||||
Change in fair value (net of $(2) of taxes) | (4 | ) | — | (4 | ) | |||||||
Balance of accumulated income, at December 31, 2017 | — | — | — | |||||||||
(1) Reclassified to aircraft fuel expense | ||||||||||||
(2) Reclassified to interest expense |
2017 | 2016 | 2015 | ||||||||||
Deferred: | ||||||||||||
Federal | $ | (361 | ) | $ | 245 | $ | 351 | |||||
State | 25 | 25 | 26 | |||||||||
Foreign | 23 | — | — | |||||||||
Deferred income tax (benefit) expense | (313 | ) | 270 | 377 | ||||||||
Current: | ||||||||||||
Federal | 94 | 129 | 20 | |||||||||
State | 18 | 26 | 16 | |||||||||
Foreign | (25 | ) | 32 | 7 | ||||||||
Current income tax expense | 87 | 187 | 43 | |||||||||
Total income tax (benefit) expense | $ | (226 | ) | $ | 457 | $ | 420 |
2017 | 2016 | |||||||||||||
Secured Debt | ||||||||||||||
Floating rate equipment notes, due through 2025(1) | $ | 153 | 4.7 | % | $ | 173 | 4.2 | % | ||||||
Fixed rate enhanced equipment notes, due through 2023(2) | 171 | 4.5 | % | 189 | 4.5 | % | ||||||||
Fixed rate equipment notes, due through 2026 | 716 | 5.4 | % | 850 | 5.5 | % | ||||||||
Fixed rate specialty bonds, due through 2036(3) | 43 | 4.9 | % | 43 | 4.9 | % | ||||||||
Capital Leases(4) | 124 | 4.5 | % | 140 | 4.3 | % | ||||||||
Total debt and capital lease obligations | 1,207 | 1,395 | ||||||||||||
Less: Current maturities | (196 | ) | (189 | ) | ||||||||||
Less: Debt acquisition cost | (8 | ) | (11 | ) | ||||||||||
Long-term debt and capital lease obligations | $ | 1,003 | $ | 1,195 |
2017 | 2016 | |||||||
Deferred tax assets: | ||||||||
Deferred revenue/gains | 95 | 121 | ||||||
Terminal 5 lease | 45 | 38 | ||||||
Employee benefits | 32 | 41 | ||||||
Foreign tax credit | 23 | — | ||||||
Rent expense | 22 | 34 | ||||||
Other | 6 | 8 | ||||||
Deferred tax assets, net | 223 | 242 | ||||||
Deferred tax liabilities: | ||||||||
Accelerated depreciation | (1,256 | ) | (1,596 | ) | ||||
Deferred tax liabilities | (1,256 | ) | (1,596 | ) | ||||
Net deferred tax liability | $ | (1,033 | ) | $ | (1,354 | ) |
As of December 31, | ||||||||
2017 | 2016 | |||||||
Fuel derivatives | ||||||||
Asset fair value recorded in prepaid expense and other(1) | $ | — | $ | 22 | ||||
Longest remaining term (months) | — | 12 | ||||||
Hedged volume (barrels, in thousands) | — | 1,920 | ||||||
Estimated amount of existing (gains) expected to be reclassified into earnings in the next 12 months | — | (22 | ) |
2017 | 2016 | 2015 | ||||||||||
Fuel derivatives | ||||||||||||
Hedge effectiveness (gains) losses recognized in aircraft fuel expense | $ | (15 | ) | $ | (9 | ) | $ | 126 | ||||
(Gains) losses on derivatives not qualifying for hedge accounting recognized in other expense | — | — | 1 | |||||||||
Hedge (gains) losses on derivatives recognized in comprehensive income | 6 | (34 | ) | 29 | ||||||||
Percentage of actual consumption economically hedged | 10 | % | 12 | % | 17 | % |
(1) | Gross asset of each contract prior to consideration of offsetting positions with each counterparty and prior to impact of collateral paid. |
2017 | 2016 | 2015 | ||||||||||
Numerator: | ||||||||||||
Net income | $ | 1,147 | $ | 759 | $ | 677 | ||||||
Effect of dilutive securities: | ||||||||||||
Interest on convertible debt, net of income taxes and profit sharing | — | 2 | 4 | |||||||||
Net income applicable to common stockholders after assumed conversions for diluted earnings per share | $ | 1,147 | $ | 761 | $ | 681 | ||||||
Denominator: | ||||||||||||
Weighted average shares outstanding for basic earnings per share | 328.7 | 326.5 | 315.1 | |||||||||
Effect of dilutive securities: | ||||||||||||
Employee stock options and restricted stock units | 1.7 | 2.1 | 2.8 | |||||||||
Convertible debt | — | 13.6 | 26.9 | |||||||||
Adjusted weighted average shares outstanding and assumed conversions for diluted earnings per share | 330.4 | 342.2 | 344.8 |
2017 | 2016 | 2015 | ||||||||||
Income tax expense at statutory rate | $ | 322 | $ | 425 | $ | 384 | ||||||
State income tax, net of federal benefit | 28 | 34 | 28 | |||||||||
Adjustment of net deferred tax liability from enacted tax rate change | (570 | ) | — | — | ||||||||
Other, net | (6 | ) | (2 | ) | 8 | |||||||
Total income tax (benefit) expense | $ | (226 | ) | $ | 457 | $ | 420 |
As of December 31, 2017 | ||||||||||||||||
Level 1 | Level 2 | Level 3 | Total | |||||||||||||
Cash equivalents | $ | 173 | $ | — | $ | — | $ | 173 | ||||||||
Available-for-sale investment securities | — | 136 | — | 136 |
As of December 31, 2016 | ||||||||||||||||
Level 1 | Level 2 | Level 3 | Total | |||||||||||||
Cash equivalents | $ | 313 | $ | — | $ | — | $ | 313 | ||||||||
Available-for-sale investment securities | 115 | 220 | — | 335 | ||||||||||||
Aircraft fuel derivatives | — | 22 | — | 22 |
Aircraft | Other | Total | ||||||||||
2018 | $ | 71 | $ | 99 | $ | 170 | ||||||
2019 | 59 | 91 | 150 | |||||||||
2020 | 57 | 74 | 131 | |||||||||
2021 | 51 | 66 | 117 | |||||||||
2022 | 45 | 62 | 107 | |||||||||
Thereafter | 139 | 378 | 517 | |||||||||
Total minimum operating lease payments | $ | 422 | $ | 770 | $ | 1,192 |
Year | Maturities | |||
2018 | $ | 194 | ||
2019 | 215 | |||
2020 | 179 | |||
2021 | 164 | |||
2022 | 142 | |||
Thereafter | 305 |
First Quarter | Second Quarter | Third Quarter | Fourth Quarter | |||||||||||||
2017 | ||||||||||||||||
Operating revenues | $ | 1,604 | $ | 1,842 | $ | 1,813 | $ | 1,756 | ||||||||
Operating income | 147 | 354 | 310 | 189 | ||||||||||||
Net income(1) | 85 | 211 | 179 | 672 | ||||||||||||
Basic earnings per share | $ | 0.25 | $ | 0.64 | $ | 0.55 | $ | 2.09 | ||||||||
Diluted earnings per share(1) | $ | 0.25 | $ | 0.64 | $ | 0.55 | $ | 2.08 | ||||||||
2016 | ||||||||||||||||
Operating revenues | $ | 1,616 | $ | 1,643 | $ | 1,732 | $ | 1,641 | ||||||||
Operating income | 349 | 313 | 354 | 296 | ||||||||||||
Net income | 207 | 181 | 199 | 172 | ||||||||||||
Basic earnings per share | $ | 0.64 | $ | 0.56 | $ | 0.61 | $ | 0.51 | ||||||||
Diluted earnings per share | $ | 0.61 | $ | 0.53 | $ | 0.58 | $ | 0.50 |
2017 | 2016 | 2015 | ||||||||||
Domestic | $ | 5,001 | $ | 4,751 | $ | 4,521 | ||||||
Caribbean & Latin America | 2,014 | 1,881 | 1,895 | |||||||||
Total | $ | 7,015 | $ | 6,632 | $ | 6,416 |
Shares | Weighted Average Grant Date Fair Value | |||||
Nonvested at beginning of year | 1.8 | $16.77 | ||||
Granted | 0.9 | 19.76 | ||||
Vested | (1.0 | ) | 14.04 | |||
Forfeited | (0.1 | ) | 19.69 | |||
Nonvested at end of year | 1.6 | $20.14 |
Shares | Weighted Average Grant Date Fair Value | |||||
Outstanding at beginning of year | 0.4 | $10.90 | ||||
Exercised | (0.4 | ) | 10.90 | |||
Outstanding at end of year | — | — | ||||
Vested at end of year | — | — |
Balance at beginning of period | Additions Charged to Costs and Expenses | Deductions | Balance at end of period | |||||||||||||
Year Ended December 31, 2017 | ||||||||||||||||
Allowance for doubtful accounts | $ | 5 | $ | — | $ | 4 | (1) | $ | 1 | |||||||
Allowance for obsolete inventory parts | 12 | 2 | — | (2) | 14 | |||||||||||
Total | 17 | 2 | 4 | 15 | ||||||||||||
Year Ended December 31, 2016 | ||||||||||||||||
Allowance for doubtful accounts | $ | 6 | $ | — | $ | 1 | (1) | $ | 5 | |||||||
Allowance for obsolete inventory parts | 10 | 2 | — | (2) | 12 | |||||||||||
Total | 16 | 2 | 1 | 17 | ||||||||||||
Year Ended December 31, 2015 | ||||||||||||||||
Allowance for doubtful accounts | $ | 6 | $ | 4 | $ | 4 | (1) | $ | 6 | |||||||
Allowance for obsolete inventory parts | 8 | 2 | — | (2) | 10 | |||||||||||
Total | 14 | 6 | 4 | 16 |
(1) | Uncollectible accounts written off, net of recoveries. |
(2) | Inventory scrapped. |
2017 | 2016 | 2015 | ||||||||||
Domestic | $ | 5,001 | $ | 4,751 | $ | 4,521 | ||||||
Caribbean & Latin America | 2,014 | 1,881 | 1,895 | |||||||||
Total | $ | 7,015 | $ | 6,632 | $ | 6,416 |
2017 | 2016 | |||||||
Available-for-sale securities | ||||||||
Time deposits | $ | 130 | $ | 160 | ||||
Debt Securities | 6 | — | ||||||
Treasury bills | — | 115 | ||||||
Commercial paper | — | 60 | ||||||
Total available-for-sale securities | 136 | 335 | ||||||
Held-to-maturity securities | ||||||||
Treasury notes | 220 | 283 | ||||||
Corporate bonds | 36 | 10 | ||||||
Total held-to-maturity securities | 256 | 293 | ||||||
TOTAL INVESTMENT SECURITIES | $ | 392 | $ | 628 |
Property and Equipment Type | Estimated Useful Life | Residual Value | |||
Aircraft | 25 years | 20 | % | ||
In-flight entertainment systems | 5-10 years | 0 | % | ||
Aircraft parts | Fleet life | 10 | % | ||
Flight equipment leasehold improvements | Lower of lease term or economic life | 0 | % | ||
Ground property and equipment | 2-10 years | 0 | % | ||
Leasehold improvements—other | Lower of lease term or economic life | 0 | % | ||
Buildings on leased land | Lease term | 0 | % |
2017 | 2016 | 2015 | ||||||||||
Unrecognized tax benefits at January 1, | $ | 26 | $ | 21 | $ | 16 | ||||||
Increases for tax positions taken during a prior period | 2 | 10 | — | |||||||||
Increases for tax positions taken during the period | 6 | 5 | 6 | |||||||||
Decreases for tax positions taken during a prior period | (3 | ) | (4 | ) | (1 | ) | ||||||
Decreases for settlement with tax authorities during the period | — | (6 | ) | — | ||||||||
Unrecognized tax benefits December 31, | $ | 31 | $ | 26 | $ | 21 |