Share-Based Compensation	3 Months Ended
Share-Based Compensation	Mar. 31, 2012
Share-based Compensation [Abstract]
Share-Based Compensation	Share-Based Compensation In February 2012, we granted 15,000 shares of restricted stock to our executive officers under the 2009 Equity Plan. The awards vest ratably over an eight year period beginning on the fourth anniversary of the grant date, and have a fair value of $40.80 per share. The fair value was determined by using the closing share price of our common stock on the date the grant was issued. During the three months ended March 31, 2012, 5,430 shares of common stock were issued in connection with the exercise of stock options and the net proceeds received were $0.1 million. The vesting requirements for 8,750 restricted shares granted to our employees were satisfied during the three months ended March 31, 2012.

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

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+ Details