Income Taxes - Unrecognized Tax Benefits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$ 16,545us-gaap_UnrecognizedTaxBenefits	$ 13,178us-gaap_UnrecognizedTaxBenefits
Increases related to prior year tax positions	314	1,489
Increases related to current year tax positions	694	2,864
Settlements	(2,499)	0
Reduction due to lapse of applicable statute of limitations	(87)	(986)
Balance at December 31	$ 14,967us-gaap_UnrecognizedTaxBenefits	$ 16,545us-gaap_UnrecognizedTaxBenefits

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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

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

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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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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.

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