Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Schedule Of Net Income Attributable To Common Stockholders

	Year Ended December 31,
	2011			2010			2009
Net income	$	258,966		$	221,393		$	52,995
Less:
Net income attributable to participating securities		(2,310	)		(2,230	)		(475	)
Net income attributable to common shareholders	$	256,656		$	219,163		$	52,520

Reconciliation Of Denominator For Basic And Diluted Earnings (Loss) Per Share

	Year Ended December 31,
	2011		2010		2009
Weighted average common shares—basic		65,927,421		65,472,875		65,323,101
Plus incremental shares from:
Assumed exercise of options		372,737		203,789		98,289
Weighted average common shares—diluted		66,300,158		65,676,664		65,421,390
Earnings per share:
Basic	$	3.89	$	3.35	$	0.80
Diluted	$	3.87	$	3.34	$	0.80