Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ 733,993	$ 623,925	$ 548,078
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted Average Number of Shares Outstanding, Basic	222,475	227,119	232,889
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	1,596	2,110	2,029
Weighted Average Number of Shares Outstanding, Diluted	224,071	229,229	234,918
Basic (in dollars per share)	$ 3.30	$ 2.75	$ 2.35
Diluted (in dollars per share)	$ 3.28	$ 2.72	$ 2.33