Income Taxes - Activity related to the Company’s unrecognized tax benefits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$ 840us-gaap_UnrecognizedTaxBenefits	$ 910us-gaap_UnrecognizedTaxBenefits		$ 1,049us-gaap_UnrecognizedTaxBenefits
Increases related to current year tax positions	0	0	0
Unrecognized Tax Benefits, Increases Resulting from Acquisition	0	0	236
Increases related to previous year tax positions	5	0	580
Reductions due to lapse of applicable statute of limitations	(362)	(48)	(256)
Reduction due to settlements	0	(22)	(699)
Balance at December 31	$ 483us-gaap_UnrecognizedTaxBenefits	$ 840us-gaap_UnrecognizedTaxBenefits	$ 910us-gaap_UnrecognizedTaxBenefits	$ 1,049us-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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-Publisher FASB

-Name Accounting Standards Codification

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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Amount of increase in unrecognized tax benefits resulting from acquisitions.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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