Earnings Per Share

12 Months Ended

Dec. 31, 2012

Earnings Per Share [Abstract]

Earnings Per Share

15. Earnings Per Share

     The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share data):

		Year Ended December 31,
		2012		2011		2010
Numerator for basic and diluted earnings
	per share - net income attributable to
	common stockholders	$	221,884	$	157,108	$	106,882
Denominator for basic earnings per
	share: weighted-average shares		224,343		173,741		127,656
Effect of dilutive securities:
	Employee stock options		231		176		125
	Non-vested restricted shares		312		246		420
	Convertible senior unsecured notes		1,067		238		7
Dilutive potential common shares			1,610		660		552
Denominator for diluted earnings per
	share: adjusted-weighted average shares		225,953		174,401		128,208
Basic earnings per share		$	0.99	$	0.90	$	0.84
Diluted earnings per share		$	0.98	$	0.90	$	0.83

The diluted earnings per share calculations exclude the dilutive effect of 182,000, 0and 280,000 stock options for the years ended December 31, 2012, 2011 and 2010, respectively, because the exercise prices were more than the average market price.The Series H Cumulative Convertible and Redeemable Preferred Stock issued in 2010 wasexcluded from the calculations for 2010 and 2011 as the effect of the conversions was anti-dilutive. The Series I Cumulative Convertible Perpetual Preferred Stock issued in 2011 was excluded from the calculations for 2011 and 2012 as the effect of the conversions was anti-dilutive.