Income Taxes Reconciliation of Total Amounts of Gross Unrecognized Tax Benefits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 6,110us-gaap_UnrecognizedTaxBenefits	$ 7,097us-gaap_UnrecognizedTaxBenefits	$ 11,669us-gaap_UnrecognizedTaxBenefits
Gross increases-tax positions in prior years	1	559	352
Gross decreases-tax positions in prior years	(333)	(369)	(273)
Gross increases-tax positions in current year	35	38	42
Settlements	0	0	(252)
Lapse of statute of limitations	(1,240)	(1,215)	(4,441)
Balance at end of period	$ 4,573us-gaap_UnrecognizedTaxBenefits	$ 6,110us-gaap_UnrecognizedTaxBenefits	$ 7,097us-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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-Name Accounting Standards Codification

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

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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.

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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.

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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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