4. STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION PLANS

Stock Repurchase Program. We currently have a stock repurchase program, approved by our Board of Directors, authorizing us to repurchase our common stock from time-to-time as market and business conditions warrant (the "Stock Repurchase Program"). We did not repurchase any shares under our Stock Repurchase Program during the six months ended June 30, 2011. During the six months ended June 30, 2010, we repurchased 1.5 million shares of our common stock under the Stock Repurchase Program for $29.3 million (weighted-average price of $19.56 per share). As of June 30, 2011, the total remaining number of shares available for repurchase under the Stock Repurchase Program totaled 4.2 million shares.

Stock Repurchases for Tax Withholdings. In addition to the above mentioned stock repurchases, during the six months ended June 30, 2011 and 2010, we repurchased from our employees and then cancelled 0.2 million shares of common stock for $4.0 million and 0.2 million shares of common stock for $4.3 million, respectively, in connection with minimum tax withholding requirements resulting from the vesting of restricted common stock under our stock incentive plans.

Equity Compensation Plans. In May 2011, our stockholders approved the amended and restated 2005 Stock Incentive Plan, which included an increase in the number of shares that may be issued under the plan of 3,400,000 shares, from 12,400,000 shares to 15,800,000 shares. Additionally in May 2011, our stockholders approved the amended and restated 1996 Employee Stock Purchase Plan, which included an increase in the number of shares reserved for sales to our employees of 750,000 shares, from 958,043 shares to 1,708,043 shares.

Stock-Based Awards. A summary of our unvested restricted common stock activity during the second quarter and six months ended June 30, 2011 is as follows:


	Quarter Ended June 30, 2011					Six Months Ended June 30, 2011
	Shares			Weighted- Average Grant Date Fair Value		Shares			Weighted- Average Grant Date Fair Value
Unvested awards, beginning		1,858,967		$	18.02		1,803,971		$	17.19
Awards granted		6,300			20.08		677,550			19.24
Awards forfeited/cancelled		(14,068	)		17.12		(40,068	)		17.41
Awards vested		(7,475	)		17.88		(597,729	)		16.89

Unvested awards, ending		1,843,724		$	18.04		1,843,724		$	18.04

Included in the awards granted during the six months ended June 30, 2011, are performance-based awards for 120,000 restricted common stock shares issued to members of executive management, which vest in equal installments over three years upon meeting either pre-established financial performance objectives or pre-established stock price objectives. The performance-based awards become fully vested upon a change in control, as defined, and the subsequent involuntary termination of employment.

All other restricted common stock shares granted during the six months ended June 30, 2011 are time-based awards, which vest annually over four years with no restrictions other than the passage of time. Certain shares of the restricted common stock become fully vested upon a change in control, as defined, and the subsequent involuntary termination of employment.

We recorded stock-based compensation expense for the second quarter of 2011 and 2010 of $3.2 million for both periods, and for the six months ended June 30, 2011 and 2010 of $6.5 million and $6.2 million, respectively.