v3.3.1.900
Income Taxes Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Schedule of Deferred Tax Assets and Liabilities [Abstract]    
Post-retirement benefit obligation $ 75,045 $ 92,995
Expenses currently not deductible 109,283 116,247
Net operating loss carryforward 211,627 228,863
Tax credit carryforward 10,343 11,509
Depreciation and amortization 7,533 11,121
Other 25,379 22,285
Valuation allowance (161,030) (159,252)
Deferred tax assets, net 278,180 323,768
Depreciation and amortization (317,464) (353,660)
Post-retirement benefit obligation (13,581) (12,116)
Inventory (17,122) (16,549)
Other (174,367) (193,618)
Total deferred tax liabilities (522,534) (575,943)
Total deferred tax liabilities, net $ (244,354) $ (252,175)