Net Income Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Numerator for Basic and Diluted Earnings per Share - [Abstract]
Net Income	$ 395,778	$ 295,574	$ 719,787	$ 429,547
Denominator for Basic Earnings per Share - [Abstract]
Weighted Average Shares	266,874,000	265,830,000	266,718,000	259,766,000
Potential Dilutive Common Shares -[Abstract]
Stock Options/SARs	1,428,000	1,807,000	1,611,000	1,891,000
Restricted Stock and Restricted Stock Units	1,683,000	1,695,000	1,754,000	1,706,000
Denominator for Diluted Earnings per Share - [Abstract]
Adjusted Diluted Weighted Average Shares	269,985,000	269,332,000	270,083,000	263,363,000
Net Income Per Share [Abstract]
Basic	$ 1.48	$ 1.11	$ 2.70	$ 1.65
Diluted	$ 1.47	$ 1.10	$ 2.67	$ 1.63
Antidilutive Stock Options and SARs excluded from Diluted Earnings Per Share Calculation	300,000	200,000	200,000	200,000