Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2013

Stock-Based Compensation [Abstract]

Employee Stock-Based Compensation Costs

	For the three months ended
	March 31,
	2013		2012
	(in thousands)
Stock-based compensation cost – expensed	$	2,994	$	2,844
Stock-based compensation cost – capitalized	$	2,862	$	2,864

Summary of Stock Option Activity, Options Outstanding

		Weighted
		Average
	Number	Exercise
	of Options	Price
Outstanding at December 31, 2012	3,649,520	$	29.84
Granted	5,210		34.84
Exercised	(451,840)		10.62
Forfeited or expired	(20,698)		35.83
Outstanding at March 31, 2013	3,182,192		32.54
Exercisable at March 31, 2013	1,923,698	$	30.61

Summary of Restricted Stock Activity and Unvested Shares

		Weighted
		Average
	Number	Grant Date
	of Shares	Fair Value
Unvested shares at December 31, 2012	1,117,515	$	35.64
Granted	6,800		35.89
Vested	(3,193)		34.95
Forfeited	(24,005)		35.92
Unvested shares at March 31, 2013	1,097,117	$	35.63