Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive loss (income), net of tax, beginning balance			$ (637,482)	$ (680,095)
OCI before reclassifications			(93,535)	27,979
Amounts reclassified from AOCI			15,912	(4,535)
Net current period other comprehensive income (loss)	$ (22,607)	$ 19,550	(77,623)	23,444
Accumulated other comprehensive loss (income), net of tax, ending balance	(715,105)	(656,651)	(715,105)	(656,651)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive loss (income), net of tax, beginning balance			(297,416)	(352,025)
OCI before reclassifications			(98,048)	42,023
Amounts reclassified from AOCI			0	(12,214)
Net current period other comprehensive income (loss)			(98,048)	29,809
Accumulated other comprehensive loss (income), net of tax, ending balance	(395,464)	(322,216)	(395,464)	(322,216)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive loss (income), net of tax, beginning balance			(10,332)	7,604
OCI before reclassifications			4,328	(14,044)
Amounts reclassified from AOCI			8,019	(3,489)
Net current period other comprehensive income (loss)			12,347	(17,533)
Accumulated other comprehensive loss (income), net of tax, ending balance	2,015	(9,929)	2,015	(9,929)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive loss (income), net of tax, beginning balance			(329,734)	(335,674)
OCI before reclassifications			185	0
Amounts reclassified from AOCI			7,893	11,168
Net current period other comprehensive income (loss)			8,078	11,168
Accumulated other comprehensive loss (income), net of tax, ending balance	$ (321,656)	$ (324,506)	$ (321,656)	$ (324,506)

Accumulated Other Comprehensive Income (Loss) [Roll Forward]

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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-Publisher FASB
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-Publisher FASB
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-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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