Income Taxes (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Abstract]
PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained	50.00%
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 8,000,000	$ 8,600,000
Unrecognized Tax Benefits, Period Increase (Decrease)	(800,000)	(2,300,000)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	5,700,000	6,700,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1,000,000	700,000	600,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	(700,000)
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	(1,700,000)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance beginning of period	13,432,000us-gaap_UnrecognizedTaxBenefits	15,723,000us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to current year	983,000	843,000
Additions for tax positions of prior years	277,000	616,000
Reductions for tax positions of prior years	0	(300,000)
Reductions due to lapse of applicable statute of limitations	(2,060,000)	(1,984,000)
Settlements	0	(1,466,000)
Balance end of period	12,632,000us-gaap_UnrecognizedTaxBenefits	13,432,000us-gaap_UnrecognizedTaxBenefits	15,723,000us-gaap_UnrecognizedTaxBenefits
Valuation Allowance [Abstract]
Valuation Allowance, Amount	$ 0	$ 0

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PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of (increase) decrease reasonably possible in the estimated lower bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

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Amount of (increase) decrease reasonably possible in the estimated upper bound of the unrecognized tax benefit for a tax position taken or expected to be taken.

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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 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 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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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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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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