Taxes - Changes in the Reserve for Income Taxes, Excluding Interest and Penalties (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Balance of reserve for income taxes	$ 4,408us-gaap_UnrecognizedTaxBenefits	$ 4,024us-gaap_UnrecognizedTaxBenefits
Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in prior periods		438
Unrecognized Tax Benefits, Period Increase (Decrease)	(226)
Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in the current period	1,095	1,048
Gross amounts of decreases in unrecognized tax benefits relating to settlements with taxing authorities	(15)	0
Gross amounts of decreases in unrecognized tax benefits as a result of the expiration of the applicable statutes of limitations	(135)	(1,102)
Balance of reserve for income taxes	$ 5,127us-gaap_UnrecognizedTaxBenefits	$ 4,408us-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.

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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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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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

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