Income Taxes (Summary Of The Provision For Income Taxes And The U.S. Federal Tax Rate) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Income Taxes [Abstract]
Income tax expense at federal statutory rate, amount	$ 21,112	$ 16,505
Income tax expense at federal statutory rate	35.00%	35.00%
Foreign income tax differential, amount	(2,716)	(1,905)
Foreign income tax differential, rate	(4.50%)	(4.00%)
State taxes, net of federal benefit, amount	792	788
State taxes, net of federal benefit, rate	1.30%	1.70%
Foreign-sourced nontaxable income, amount	(1,894)	(764)
Foreign-sourced nontaxable income, rate	(3.10%)	(1.60%)
Other, amount	951	199
Other, rate	1.50%	0.30%
Provision for taxes	$ 18,245	$ 14,823
Provision for income taxes and rate	30.20%	31.40%