Income Taxes (Deferred Tax Liabilities and Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax liabilities:
Depreciation	$ (77,415)	$ (93,475)
Deferred profit (for tax purposes) on sale to finance subsidiary	(60,340)	(98,247)
Lease revenue and related depreciation	(133,908)	(137,665)
Intangible assets	(106,488)	(113,128)
Other	(22,468)	(27,340)
Gross deferred tax liabilities	(400,619)	(469,855)
Deferred tax assets:
Nonpension postretirement benefits	48,387	71,101
Pension	66,270	105,564
Inventory and equipment capitalization	11,380	13,318
Restructuring charges	12,476	6,980
Long-term incentives	11,544	17,923
Net operating loss	108,006	97,194
Tax credit carry forwards	82,285	53,181
Tax uncertainties gross-up	9,920	18,273
Other	51,436	79,799
Gross deferred tax assets	401,704	463,333
Less: Valuation allowance	(178,156)	(127,095)
Net deferred tax assets	223,548	336,238
Total deferred taxes, net	$ (177,071)	$ (133,617)

The sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset and the tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

No definition available.