Benefit Plans Benefit Plans (Detail 12) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	$ 904,435	$ 825,774
Foreign Currency Exchange Rate Changes, Plan Assets	(79,810)	17,881
Fair Value of Plan Assets, Ending	883,223	904,435
Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	101,923	99,697
Defined Benefit Plan, Actual Return on Plan Assets Still Held	7,442	1,040
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		4,811
Defined Benefit Plan,Purchases, Total	28,012	11,919
Defined Benefit Plan Sales, Total	(21,703)	(13,210)
Foreign Currency Exchange Rate Changes, Plan Assets	(9,950)	2,477
Fair Value of Plan Assets, Ending	110,535	101,923
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, Ending	80,951	77,312
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	77,312	74,985
Defined Benefit Plan, Actual Return on Plan Assets Still Held	4,456	1,420
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		4,811
Defined Benefit Plan,Purchases, Total	22,867	11,792
Defined Benefit Plan Sales, Total	(21,649)	(12,691)
Foreign Currency Exchange Rate Changes, Plan Assets	(6,846)	1,806
Fair Value of Plan Assets, Ending	80,951	77,312
Real Asset Mutual Funds, Commodities
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Ending	52,234	49,752
Real Asset Mutual Funds, Commodities \| Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	23,136	22,986
Defined Benefit Plan, Actual Return on Plan Assets Still Held	2,952	(449)
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		0
Defined Benefit Plan,Purchases, Total	5,030	0
Defined Benefit Plan Sales, Total	0	0
Foreign Currency Exchange Rate Changes, Plan Assets	(2,922)	599
Fair Value of Plan Assets, Ending	28,196	23,136
Fixed Income Mutual Funds, Insurance Contracts
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Ending	24,676	26,108
Fixed Income Mutual Funds, Insurance Contracts \| Level 3
Rollforward of Activity for Level 3 Asset Categories [Roll Forward]
Fair Value of Plan Assets, Beginning	1,475	1,726
Defined Benefit Plan, Actual Return on Plan Assets Still Held	34	69
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period		0
Defined Benefit Plan,Purchases, Total	115	127
Defined Benefit Plan Sales, Total	(54)	(519)
Foreign Currency Exchange Rate Changes, Plan Assets	(182)	72
Fair Value of Plan Assets, Ending	$ 1,388	$ 1,475

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

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=35743120&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=35743120&loc=d3e2446-114920

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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 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: 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=29635418&loc=d3e12355-114930

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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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