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Income Taxes (Summary of Unrecognized Tax Benefits and Temporary Differences) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Unrecognized tax benefits |  |
Balance at the beginning of the period | $ 274 | $ 464
Increases related to current year tax positions | 4 | 5
Decreases due to tax positions expired | (72) | (195)
Balance at the end of the period | 206 | 274
Uncertain tax positions, reserved for tax exposure in Europe | 0 |
Deferred tax assets: |  |
Unearned lease revenue | 1,839 | 1,511
State taxes | 1,035 | 944
Reserves and allowances | 1,659 | 898
Other accruals | 2,501 | 1,767
Alternative minimum tax credit | 377 | 377
Net operating loss carry forward | 35,693 | 35,827
Charitable contributions | 52 | 42
Total deferred tax assets | 43,156 | 41,366
Less: valuation allowance | (1,280) | (1,280)
Net deferred tax assets | 41,876 | 40,086
Deferred tax liabilities: |  |
Depreciation and impairment on aircraft engines and equipment | (147,827) | (137,496)
Other deferred tax assets (liabilities) | 422 | 981
Net deferred tax liabilities | (147,405) | (136,515)
Other comprehensive income, deferred tax asset | 551 | 275
Net deferred tax liabilities | (104,978) | $ (96,154)
Additional tax benefits reflected in net operating tax loss carryforwards pursuant to SFAS 123R | 3,000 |
Tax effects of windfalls included in net operating loss carryforwards | 1,000 |
Federal |  |
Deferred tax liabilities: |  |
Operating loss carryforwards | 105,000 |
State |  |
Deferred tax liabilities: |  |
Operating loss carryforwards | $ 4,700 |

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