Income Taxes Provision for Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current Federal	$ 3,582	$ 5,652	$ 5,105
Current State	3,752	3,686	2,728
Deferred Federal	17,382	12,578	14,037
Deferred State	906	1,535	2,759
Total United States income taxes	25,622	23,451	24,629
Current Foreign	9,907	6,488	8,967
Deferred Foreign	10,873	8,592	(3,432)
Total foreign income taxes	20,780	15,080	5,535
Provision for income taxes	$ 46,402	$ 38,531	$ 30,164