Income Taxes Schedule of Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning	$ 12,743us-gaap_UnrecognizedTaxBenefits	$ 12,339us-gaap_UnrecognizedTaxBenefits	$ 17,335us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to the current year	1,894	1,866	711
Additions for tax positions of prior years	1,722	4,106	956
Settlements	(503)	(3,134)	(2,620)
Reductions for tax positions of prior years	(152)	(1,163)	(3,590)
Reductions due to lapse of applicable statutes	(1,838)	(1,314)	(449)
Adjustments due to foreign exchange rate movement	(502)	43	(4)
Ending	$ 13,364us-gaap_UnrecognizedTaxBenefits	$ 12,743us-gaap_UnrecognizedTaxBenefits	$ 12,339us-gaap_UnrecognizedTaxBenefits

Unrecognized tax benefits adjustments due to foreign exchange rate movement

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15A

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