Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Statement Income Taxes Details [Abstract]
Income Tax Expense (Benefit)	$ 81,713	$ 88,059	$ 183,392	$ 238,477
Effective Income Tax Rate, Continuing Operations	35.40%	35.10%	36.30%	35.90%