Benefit Plans Benefit Plans (Detail 8) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amortization of Net Prior Service Cost (Credit)	$ (7,338)
Amortization of Net Gains (Losses)	26,174
Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	18,836
Domestic Plan [Member] \| Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amortization of Net Prior Service Cost (Credit)	0
Amortization of Net Gains (Losses)	5,804
Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	5,804
Domestic Plan [Member] \| Other Postretirement Benefits Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amortization of Net Prior Service Cost (Credit)	(372)
Amortization of Net Gains (Losses)	(1,250)
Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	(1,622)
Foreign Plan [Member] \| Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Amortization of Net Prior Service Cost (Credit)	(6,966)
Amortization of Net Gains (Losses)	21,620
Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	$ 14,654

Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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