Employee Benefits (Narrative Defined Contribution Plans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Foreign Postretirement Benefit Plan [Member]
Defined Contribution Plan [Line Items]
Defined contribution savings plan expense	$ 1,912	$ 416
Defined Contribution Savings Plan [Member] \| U. S. Plans [Member]
Defined Contribution Plan [Line Items]
Maximum employee contribution as a percentage of annual compensation	100.00%
Matching percentage by company of first 4% of employee contribution	100.00%
Percentage of employee contribution fully matched by company	4.00%
Employer contributions to plans	$ 7,594	6,856	$ 6,022
Defined Contribution Retirement Plan [Member] \| U. S. Plans [Member]
Defined Contribution Plan [Line Items]
Employer contributions to plans	$ 11,715	$ 8,309	$ 6,227
Length of service required to be eligible for annual retirement contributions (in years)	1 year

The amount of the cost recognized during the period for defined contribution plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

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- Definition

Eligibility requirements, length of service required for annual retirement contribution

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- Definition

Maximum Employee Contribution As Percentage Of Annual Compensation

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- Definition

Percentage Of Employee Contribution Fully Matched By Company

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