Income Taxes Deferred Income Tax Assets and Liabilities Recorded on Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Accrued employee benefits		$ 28,167	$ 20,834
Accrued expenses		33,048	2,379
Operating loss carryovers		131,985	82,017
Pensions		111,059	79,113
Intangibles		0	5,732
Tax credit carryovers		2,555	34,469
Other		32,725	20,227
Gross deferred tax assets		339,539	244,771
Valuation allowance		(85,370)	(30,768)	$ (33,757)	$ (49,562)
Deferred tax assets		254,169	214,003
Deferred tax liabilities:
Depreciation		(378,669)	(190,280)
Intangibles		(488,855)	0
Foreign currency translation adjustments		0	(4,752)
Other		(46,937)	(18,420)
Deferred tax liabilities		(914,461)	(213,452)
Net deferred tax (liabilities) assets			551
Current deferred tax assets	[1]	0	1,801
Current deferred tax liabilities		0	(6,806)
Noncurrent deferred tax assets	[2]	76,025	62,440
Noncurrent deferred tax liabilities		(736,317)	(56,884)
Net deferred tax (liabilities) assets			$ 551
Deferred Tax Liabilities, Net		$ (660,292)

[1] See Note 1, “Summary of Significant Accounting Policies” and Note 20, “Income Taxes.”

[2] See Note 1, “Summary of Significant Accounting Policies” and Note 20, “Income Taxes.”