Income Taxes Company's uncertain tax positions (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Company's uncertain tax positions [Abstract]
Balance as of the beginning of the year	$ 2,138,000us-gaap_UnrecognizedTaxBenefits	$ 3,382,000us-gaap_UnrecognizedTaxBenefits
Tax positions related to current year:
Additions	76,000	31,000
Reductions	(48,000)	0
Tax positions related to prior years:
Additions	0	0
Reductions	(232,000)	(571,000)
Settlements	0	0
Lapses in statute of limitations	(575,000)	(704,000)
Balance as of the end of the year	1,359,000us-gaap_UnrecognizedTaxBenefits	2,138,000us-gaap_UnrecognizedTaxBenefits	3,382,000us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	469,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	99,000
Unrecognized tax benfits, reduction in accrued interest and penalties	$ 35,000	$ 6,000	$ 71,000

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Unrecognized tax benfits, reduction in accrued interest and penalties

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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 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 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 accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the 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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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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