Earnings (Losses) Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Earnings (losses) per share computations
Income (loss) from continuing operations, net of tax	$ 97,172	$ 142,618
Less: Net (income) loss attributable to noncontrolling interest	(97)	267
Less: earnings allocated to unvested shareholders	(814)
Adjusted income (loss) from continuing operations - basic and diluted	96,261	142,885
Income (loss) from discontinued operations, net of tax	$ 2,046	$ (8,795)
Earnings (losses) per share:
Basic from continuing operations (in dollars per share)	$ 0.33	$ 0.50
Basic from discontinued operations (in dollars per share)	$ 0.01	$ (0.04)
Total Basic (in dollars per share)	$ 0.34	$ 0.46
Diluted from continuing operations (in dollars per share)	$ 0.33	$ 0.49
Diluted from discontinued operations (in dollars per share)		$ (0.03)
Total Diluted (in dollars per share)	$ 0.33	$ 0.46
Shares (denominator):
Weighted-average number of shares outstanding - basic	291,687,000	288,538,000
Net effect of dilutive stock options, warrants and restricted stock awards based on the if-converted method (in shares)	2,483,000	3,171,000
Weighted-average number of shares outstanding - diluted	294,170,000	291,709,000
Average number of options and warrants excluded from diluted earnings (losses) per share (in shares)	12,452,263	11,763,048