Benefit Plans Benefit Plans (Detail 10) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	$ 883,223	$ 904,435
Foreign Currency Exchange Rate Changes, Plan Assets	(9,323)	(79,810)
Fair Value of Plan Assets, Ending	844,715	883,223
Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	110,535	101,923
Defined Benefit Plan, Actual Return on Plan Assets Still Held	8,883	7,442
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		4,811
Defined Benefit Plan,Purchases, Total	12,990	28,012
Defined Benefit Plan Sales, Total	(8,317)	(21,703)
Foreign Currency Exchange Rate Changes, Plan Assets	(477)	(9,950)
Fair Value of Plan Assets, Ending	123,614	110,535
Other Types of Investments, Multi-Strategy Fund of Hedge Funds
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	80,951
Fair Value of Plan Assets, Ending	88,742	80,951
Other Types of Investments, Multi-Strategy Fund of Hedge Funds \| Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	80,951	77,312
Defined Benefit Plan, Actual Return on Plan Assets Still Held	6,453	4,456
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		4,811
Defined Benefit Plan,Purchases, Total	9,980	22,867
Defined Benefit Plan Sales, Total	(8,317)	(21,649)
Foreign Currency Exchange Rate Changes, Plan Assets	(325)	(6,846)
Fair Value of Plan Assets, Ending	88,742	80,951
Real Asset Mutual Funds, Commodities
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	52,234
Fair Value of Plan Assets, Ending	58,477	52,234
Real Asset Mutual Funds, Commodities \| Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	28,196	23,136
Defined Benefit Plan, Actual Return on Plan Assets Still Held	2,408	2,952
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		0
Defined Benefit Plan,Purchases, Total	2,911	5,030
Defined Benefit Plan Sales, Total	0	0
Foreign Currency Exchange Rate Changes, Plan Assets	(10)	(2,922)
Fair Value of Plan Assets, Ending	33,505	28,196
Fixed Income Mutual Funds, Insurance Contracts
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	24,676
Fair Value of Plan Assets, Ending	21,718	24,676
Fixed Income Mutual Funds, Insurance Contracts \| Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	1,388	1,475
Defined Benefit Plan, Actual Return on Plan Assets Still Held	22	34
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		0
Defined Benefit Plan,Purchases, Total	99	115
Defined Benefit Plan Sales, Total	0	(54)
Foreign Currency Exchange Rate Changes, Plan Assets	(142)	(182)
Fair Value of Plan Assets, Ending	$ 1,367	$ 1,388

Purchases of plan assets that occurred during the period.

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- Definition

Sale of plan assets that occurred during the period.

+ References

No definition available.

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- Definition

Rollforward of Activity for Level 3 Asset Categories

+ References

No definition available.

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- Definition

Actual return on plan assets, separately identifying the amount related to assets sold during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(02)(A)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(iv)(02)(A)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ References

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

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