Employee Benefit Plan	12 Months Ended
Dec. 31, 2011
Employee Benefit Plan [Abstract]
Employee Benefit Plan	Note M — Employee Benefit Plan We sponsor a defined contribution pension plan under Section 401(k) of the Internal Revenue Code for all employees who have completed at least three months of service. Employees may elect to contribute up to 50% of their eligible compensation on a pre-tax basis, subject to limitations. We may make discretionary matching contributions to the 401(k) plan. For the years ended December 31, 2011, 2010 and 2009, we made matching cash contributions of $5.9 million, $5.8 million and $5.6 million, respectively, which represents 50% of the employees' contributions to the 401(k) plan up to an amount not to exceed 4% of each employee's respective compensation. Employees are permitted to elect to purchase our common stock as part of their 401(k) plan. As of December 31, 2011, 2010 and 2009, 12.0%, 12.0%, and 9.0%, respectively, of the total plan assets consisted of our common stock.

Employee Benefit Plan

12 Months Ended

Dec. 31, 2011

Note M — Employee Benefit Plan

We sponsor a defined contribution pension plan under Section 401(k) of the Internal Revenue Code for all employees who have completed at least three months of service. Employees may elect to contribute up to 50% of their eligible compensation on a pre-tax basis, subject to limitations. We may make discretionary matching contributions to the 401(k) plan. For the years ended December 31, 2011, 2010 and 2009, we made matching cash contributions of $5.9 million, $5.8 million and $5.6 million, respectively, which represents 50% of the employees' contributions to the 401(k) plan up to an amount not to exceed 4% of each employee's respective compensation. Employees are permitted to elect to purchase our common stock as part of their 401(k) plan. As of December 31, 2011, 2010 and 2009, 12.0%, 12.0%, and 9.0%, respectively, of the total plan assets consisted of our common stock.