Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2011

Share-Based Compensation [Abstract]

Summary of stock option activity

	Stock      Options			Weighted- Average Exercise Price
Outstanding at December 31, 2010		3,323		$	16.45
Granted		894		$	15.98
Exercised		(262	)	$	9.90
Canceled		(3	)	$	17.04
Outstanding at September 30, 2011		3,952		$	16.78
Exercisable at September 30, 2011		2,719		$	17.00
Vested and expected to vest at September 30, 2011		3,896		$	16.78

Assumptions used to determine fair value of options granted

Expected volatility (1)	41.6%
Weighted-average volatility (1)	42.0%
Expected dividends	0.0%
Expected term	4.85 years
Risk-free rate (2)	0.94%

⁽¹⁾  We estimated the volatility of our common stock on the date of grant based on using both historical and implied volatilities.

⁽²⁾  The risk-free interest rate is based on the implied yield in effect at the time of option grant on U.S. Treasury zero-coupon issues with equivalent remaining terms.

Summary of nonvested stock activity

	Shares			Grant Date Weighted- Average Fair Value Per Share
Outstanding at December 31, 2010		686,511		$	26.16
Granted		1,225,046		$	20.00
Vested		(334,370	)	$	28.84
Forfeited/Canceled		(2,275	)	$	30.35
Outstanding at September 30, 2011		1,574,912		$	20.80