Employee Retirement Plan	12 Months Ended
Employee Retirement Plan	Dec. 31, 2012
Employee Retirement Plan [Abstract]
Employee Retirement Plan	Note 12 – Employee retirement plan We have a defined contribution retirement plan pursuant to Section 401(k) of the Internal Revenue Code. Substantially all domestic employees with at least 30 days of continuous service are eligible to participate and may contribute up to 15% of their compensation. The Board of Directors has elected to make matching contributions equal to 50% of employee contributions, which may be applied to a maximum of 6% of each participant’s compensation. Employees are eligible for matching contributions after one year of continuous service. Company contributions vest immediately. Our policy prohibits participants from direct investment in shares of our common stock within the plan. Company contributions charged to expense were $5.3 million, $4.7 million and $4.4 million in 2012, 2011 and 2010, respectively.

The entire disclosure for pension and other postretirement benefits.

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