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Asset Impairment Charges and Facility Closing and Reorganization Costs - Facility Closing and Reorganization Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Reserve [Roll Forward]
Charges and Adjustments	$ (2,679)	$ 7,844	$ 73,444	$ 22,947
Cash charges:
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			8,469
Charges and Adjustments			34,582
Payments			(16,703)
Accrued charges at end of period	26,348		26,348
Cash charges: \| Workforce reduction costs
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			5,863
Charges and Adjustments			30,318
Payments			(11,508)
Accrued charges at end of period	24,673		24,673
Cash charges: \| Shutdown costs
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			0
Charges and Adjustments			3,784
Payments			(3,784)
Accrued charges at end of period	0		0
Cash charges: \| Lease obligations after shutdown
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			2,606
Charges and Adjustments			74
Payments			(1,005)
Accrued charges at end of period	1,675		1,675
Cash charges: \| Other
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			0
Charges and Adjustments			406
Payments			(406)
Accrued charges at end of period	$ 0		0
Non-cash charges:
Restructuring Reserve [Roll Forward]
Charges and Adjustments			38,862
Non-cash charges: \| Other
Restructuring Reserve [Roll Forward]
Charges and Adjustments			138
Non-cash charges: \| Write-down of assets
Restructuring Reserve [Roll Forward]
Charges and Adjustments			44,700
Non-cash charges: \| Gain on sale/disposal of related assets
Restructuring Reserve [Roll Forward]
Charges and Adjustments			$ (5,976)