Retirement Plan	12 Months Ended
Dec. 31, 2010
Compensation and Retirement Disclosure [Abstract]
Retirement Plan	(8) Retirement Plans The Company sponsors a single employer 401(k) plan for employees who become eligible upon the date of hire. The plan allows for contributions to be made at each compensation calculation period based on the annual discretionary contribution rate. Contributions of $3.3 million, $2.5 million and $2.3 million were made to the plan for the years ended December 31, 2012, 2011 and 2010, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

No definition available.

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