Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Income Tax Contingency [Line Items]
PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained			50.00%
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 9,900,000		$ 9,900,000		$ 11,700,000
Unrecognized Tax Benefits, Period Increase (Decrease)	(1,600,000)	(2,100,000)	(2,700,000)	(3,200,000)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	7,600,000		7,600,000		9,200,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	800,000	1,000,000	1,500,000	1,800,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	700,000		700,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	1,700,000		1,700,000
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance beginning of period			18,140,000
Additions based on tax positions related to current year			577,000
Additions for tax positions of prior years			0
Reductions for tax positions of prior years			(15,000)
Reductions due to lapse of applicable statute of limitations			(3,278,000)
Settlements			0
Balance end of period	15,424,000		15,424,000
Valuation Allowance [Abstract]
Valuation Allowance, Amount	$ 1,100,000		$ 1,100,000