Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2012

Earnings Per Share [Abstract]

Comparison Of Basic And Diluted Earnings Per Share

	Year Ended December 31,
	2012		2011		2010
Basic earnings per share:
Net income	$	493,007	$	274,548	$	665,005
Weighted average common shares outstanding		36,057,145		38,093,351		46,491,279
Basic earnings per share	$	13.67	$	7.21	$	14.30

		Year Ended December 31,
		2012		2011		2010
Diluted earnings per share:
Net income		$	493,007	$	274,548	$	665,005
Weighted average common shares outstanding			36,057,145		38,093,351		46,491,279
Share equivalents:
Warrants and options			435,334		387,549		1,668,262
RSU and LTIP awards			575,755		1,185,764		1,753,395
Employee share purchase plan			1,651		1,241		381
Weighted average common shares and common share equivalents
	outstanding - diluted		37,069,885		39,667,905		49,913,317
Diluted earnings per share		$	13.30	$	6.92	$	13.32