Equity (Tables)

6 Months Ended

Jun. 30, 2011

Equity

Schedule of equity-based compensation expense

	Three months ended				Six months ended
	June 30,				June 30,
	2011		2010		2011		2010
Equity-based compensation expense	$	4,063	$	2,523	$	7,161	$	4,389

Summary of restricted stock awards and restricted stock unit activity

	Shares (000’s)		Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2010	616		$	19.06
Granted	271		51.36
Vested	(156	)	13.78
Forfeited (including cancelled awards)	(4	)	21.93
Nonvested at June 30, 2011	727		$	32.23

Summary of stock option awards activity

	Shares (000s)		Weighted- Average Exercise Price		Aggregate Intrinsic Value (000s)		Weighted- Average Remaining Contractual Life (in years)
Outstanding at December 31, 2010	2,569		$	19.71
Granted	354		51.00
Exercised	(560	)	15.67
Forfeited (including cancelled options)	(31	)	30.37
Outstanding at June 30, 2011	2,332		$	25.28	$	52,117	6.3
Options exercisable at June 30, 2011	1,050		$	17.65	$	30,839	4.8