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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		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Reserve [Roll Forward]
Charges and Adjustments	$ 67,661	$ 5,817	$ 76,123	$ 15,103
Cash charges:
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			8,469
Charges and Adjustments			32,389
Payments			(7,714)
Accrued charges at end of period	33,144		33,144
Cash charges: \| Workforce reduction costs
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			5,863
Charges and Adjustments			30,318
Payments			(5,019)
Accrued charges at end of period	31,162		31,162
Cash charges: \| Shutdown costs
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			0
Charges and Adjustments			1,833
Payments			(1,833)
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			48
Payments			(672)
Accrued charges at end of period	1,982		1,982
Cash charges: \| Other
Restructuring Reserve [Roll Forward]
Accrued charges at beginning of period			0
Charges and Adjustments			190
Payments			(190)
Accrued charges at end of period	$ 0		0
Non-cash charges:
Restructuring Reserve [Roll Forward]
Charges and Adjustments			43,734
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			$ (966)