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Asset Impairment Charges and Facility Closing and Reorganization Costs - Facility Closing and Reorganization Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Reserve [Roll Forward]
Charges and Adjustments	$ 5,817	$ (1,400)	$ 15,103	$ (234)
Restructuring Charges, Cash
Restructuring Reserve [Roll Forward]
Accrued Charges at Beginning Balance			7,542
Charges and Adjustments			10,350
Payments			(7,106)
Accrued Charges at Ending Balance	10,786		10,786
Restructuring Charges, Cash \| Workforce reduction costs
Restructuring Reserve [Roll Forward]
Accrued Charges at Beginning Balance			3,610
Charges and Adjustments			7,464
Payments			(3,572)
Accrued Charges at Ending Balance	7,502		7,502
Restructuring Charges, Cash \| Shutdown costs
Restructuring Reserve [Roll Forward]
Accrued Charges at Beginning Balance			0
Charges and Adjustments			2,557
Payments			(2,557)
Accrued Charges at Ending Balance	0		0
Restructuring Charges, Cash \| Lease obligations after shutdown
Restructuring Reserve [Roll Forward]
Accrued Charges at Beginning Balance			3,932
Charges and Adjustments			166
Payments			(814)
Accrued Charges at Ending Balance	3,284		3,284
Restructuring Charges, Cash \| Other
Restructuring Reserve [Roll Forward]
Accrued Charges at Beginning Balance			0
Charges and Adjustments			163
Payments			(163)
Accrued Charges at Ending Balance	$ 0		0
Restructuring Charges, Noncash Charges
Restructuring Reserve [Roll Forward]
Charges and Adjustments			4,753
Restructuring Charges, Noncash Charges \| Other
Restructuring Reserve [Roll Forward]
Charges and Adjustments			8
Restructuring Charges, Noncash Charges \| Write-down of assets
Restructuring Reserve [Roll Forward]
Charges and Adjustments			4,678
Restructuring Charges, Noncash Charges \| Loss on sale of related assets
Restructuring Reserve [Roll Forward]
Charges and Adjustments			$ 67