Income Taxes - Unrecognized Tax Benefits (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning of year	$ 1,964,000us-gaap_UnrecognizedTaxBenefits	$ 2,530,000us-gaap_UnrecognizedTaxBenefits	$ 4,376,000us-gaap_UnrecognizedTaxBenefits
Additions for tax positions taken in prior years	72,000	166,000	0
Reductions for tax positions taken in prior years	0	(472,000)	(972,000)
Additions for tax positions related to the current year	821,000	54,000	0
Lapses of statutes of limitations	(89,000)	(314,000)	(874,000)
Unrecognized tax benefits, end of year	2,768,000us-gaap_UnrecognizedTaxBenefits	1,964,000us-gaap_UnrecognizedTaxBenefits	2,530,000us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits that would impact effective tax rate, if recognized	2,500,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	400,000	0	100,000
Cumulative liability for interest and penalties related to uncertain tax positions	2,000,000	1,600,000
Previously unrecognized tax benefit likely to be recognized within the next 12 months	$ 300,000

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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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 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 expense 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 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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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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