Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share (Tables) [Abstract]

Computation of basic and diluted earnings per share

		Year Ended December 31,
		2011		2010		2009
Numerator for basic and diluted earnings
	per share - net income attributable to
	common stockholders	$	157,108	$	106,882	$	171,190
Denominator for basic earnings per
	share - weighted average shares		173,741		127,656		114,207
Effect of dilutive securities:
	Employee stock options		176		125		0
	Non-vested restricted shares		246		420		405
	Convertible senior unsecured notes		238		7		0
Dilutive potential common shares			660		552		405
Denominator for diluted earnings per
	share - adjusted weighted average shares		174,401		128,208		114,612
Basic earnings per share		$	0.90	$	0.84	$	1.50
Diluted earnings per share		$	0.90	$	0.83	$	1.49