Income Taxes (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of beginning and ending balance of unrecognized tax benefits
Balance at the beginning of the period	$ 26,564,000us-gaap_UnrecognizedTaxBenefits	$ 22,245,000us-gaap_UnrecognizedTaxBenefits	$ 64,555,000us-gaap_UnrecognizedTaxBenefits
Increases related to current year tax positions	1,050,000	1,050,000
Increases related to prior year tax positions	653,000	3,760,000	741,000
Decreases related to prior year tax positions	(2,298,000)	(491,000)	(40,741,000)
Settlements with taxing authorities	(8,631,000)		(2,310,000)
Balance at the end of the period	17,338,000us-gaap_UnrecognizedTaxBenefits	26,564,000us-gaap_UnrecognizedTaxBenefits	22,245,000us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits that, if recognized, would impact effective tax rate	12,500,000
Unrecognized tax benefits from the reduction of interest expense	1,100,000
Accrued interest and penalties	5,500,000
Expected payment of taxes as a result of audit settlement, lower bound	0
Expected payment of taxes as a result of audit settlement, upper bound	$ 8,100,000

Amount of increase in unrecognized tax benefits resulting from the reduction of interest expense.

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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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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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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

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