Income Taxes (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Income Taxes
Tax reserves related to current year uncertain tax positions	$ 2,500,000
Accrued interest related to current year uncertain tax positions	2,500,000
Tax reserves related to prior year uncertain tax positions	5,900,000
Accrued interest related to prior year uncertain tax positions	5,900,000
Previously recorded tax reserves for uncertain tax positions that have settled and/or closed	7,700,000
Previously recorded accrued interest for uncertain tax positions that have settled and/or closed	1,900,000
Federal deferred tax benefit in the current year associated with its uncertain tax positions	400,000
Tax positions that, if reversed, would affect the effective tax rate	19,900,000	21,500,000
Currency translation adjustments for foreign currency tax positions	899,000	(39,000)
Interest and penalties recognized, net of deferred taxes	88,000	300,000
Reductions in previously accrued interest and penalties	1,300,000
Prepaid income taxes	68,400,000
Net tax benefit in connection with uncertain tax positions	$ 1,600,000