Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2013

Stock-Based Compensation [Abstract]

Employee Stock-Based Compensation Costs

	For the three months ended				For the six months ended
	June 30,				June 30,
	2013		2012		2013		2012
	(in thousands)
Stock-based compensation cost – expensed	$	2,968	$	2,705	$	5,962	$	5,549
Stock-based compensation cost – capitalized	$	2,872	$	2,442	$	5,734	$	5,306

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	(466,887)		11.32
Forfeited or expired	(39,369)		37.95
Outstanding at June 30, 2013	3,148,474		32.50
Exercisable at June 30, 2013	1,931,580	$	30.62

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	13,540		36.60
Vested	(26,044)		36.17
Forfeited	(41,501)		35.88
Unvested shares at June 30, 2013	1,063,510	$	35.63