Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in our liability for unrecognized gross tax benefits
Balance at beginnng of year	$ 5,003us-gaap_UnrecognizedTaxBenefits	$ 4,129us-gaap_UnrecognizedTaxBenefits	$ 2,522us-gaap_UnrecognizedTaxBenefits
Tax position of current year	593	632	145
Tax position of prior years	825	506	2,988
Statute expirations	(151)	(264)	(713)
Settlements	0	0	(404)
Tax positions of prior years	0	0	(409)
Balance at end of year	$ 6,270us-gaap_UnrecognizedTaxBenefits	$ 5,003us-gaap_UnrecognizedTaxBenefits	$ 4,129us-gaap_UnrecognizedTaxBenefits

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

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

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