Income Taxes - Unrecognized Tax Benefit (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Gross unrecognized tax benefits at beginning of year	$ 14,824us-gaap_UnrecognizedTaxBenefits	$ 16,386us-gaap_UnrecognizedTaxBenefits	$ 21,240us-gaap_UnrecognizedTaxBenefits
Increases in tax positions for prior years	0	2,692	623
Decreases in tax positions for prior years	(525)	0	(1,287)
Decreases from lapse in statute of limitations	(7,275)	(2,670)	(4,190)
Settlements	0	(1,584)	0
Gross unrecognized tax benefits at end of year	$ 7,024us-gaap_UnrecognizedTaxBenefits	$ 14,824us-gaap_UnrecognizedTaxBenefits	$ 16,386us-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

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

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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

+ 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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