Income Taxes (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of changes in the balance of unrecognized tax benefits
Beginning balance	$ 1,142us-gaap_UnrecognizedTaxBenefits	$ 1,744us-gaap_UnrecognizedTaxBenefits	$ 1,813us-gaap_UnrecognizedTaxBenefits
Increases in tax positions for prior years	91	53	34
Increases in tax positions for current year	189	103	611
Settlements	0	(716)	(704)
Expirations of statutes	0	(42)	(10)
Ending balance	$ 1,422us-gaap_UnrecognizedTaxBenefits	$ 1,142us-gaap_UnrecognizedTaxBenefits	$ 1,744us-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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