Retirement and Deferred Compensation Plans	12 Months Ended
Dec. 31, 2012
Compensation and Retirement Disclosure [Abstract]
Retirement and Deferred Compensation Plans	Retirement and Deferred Compensation Plans Retirement Plan. The Company maintains a 401(k) retirement plan for its employees. Under the plan, eligible employees may elect to defer a portion of their earnings up to the maximum allowed by regulations promulgated by the Internal Revenue Service (“IRS”). The 2012 annual 401(k) deferral limit for employees under age 50 was $17,000. Employees turning age 50 or over in 2012 could defer up to $22,500 in 2012. The Company makes matching contributions to the plan equal to 100% on the first 15% of employee deferred wages. All matching contributions are in Company stock. For 2012, 2011 and 2010, the Company satisfied its matching obligations related to employee contributions with cash purchases of Company stock. For 2012, 2011 and 2010, retirement plan expense was approximately $11.4 million, $7.4 million and $8.7 million, respectively. Deferred Compensation Plan. Effective February 1, 2007 the Company established a non-qualified deferred compensation plan that allows eligible highly compensated employees to elect to defer income exceeding the IRS annual limitations on qualified 401(k) retirement plans. The Company makes matching contributions on non-qualified contributions up to a maximum of 15% of employee compensation. For 2012, 2011 and 2010, employer contributions were approximately $3.5 million, $3.1 million and $2.8 million, respectively. Any assets placed in trust by the Company to fund future obligations of the Company’s non-qualified deferred compensation plan are subject to the claims of creditors in the event of insolvency or bankruptcy, and participants are general creditors of the Company as to their own deferred compensation in, and the Company’s contributions to, the plan.

Retirement and Deferred Compensation Plans

Retirement Plan. The Company maintains a 401(k) retirement plan for its employees. Under the plan, eligible employees may elect to defer a portion of their earnings up to the maximum allowed by regulations promulgated by the Internal Revenue Service (“IRS”). The 2012 annual 401(k) deferral limit for employees under age 50 was $17,000. Employees turning age 50 or over in 2012 could defer up to $22,500 in 2012. The Company makes matching contributions to the plan equal to 100% on the first 15% of employee deferred wages. All matching contributions are in Company stock. For 2012, 2011 and 2010, the Company satisfied its matching obligations related to employee contributions with cash purchases of Company stock. For 2012, 2011 and 2010, retirement plan expense was approximately $11.4 million, $7.4 million and $8.7 million, respectively.

Deferred Compensation Plan. Effective February 1, 2007 the Company established a non-qualified deferred compensation plan that allows eligible highly compensated employees to elect to defer income exceeding the IRS annual limitations on qualified 401(k) retirement plans. The Company makes matching contributions on non-qualified contributions up to a maximum of 15% of employee compensation. For 2012, 2011 and 2010, employer contributions were approximately $3.5 million, $3.1 million and $2.8 million, respectively.

Any assets placed in trust by the Company to fund future obligations of the Company’s non-qualified deferred compensation plan are subject to the claims of creditors in the event of insolvency or bankruptcy, and participants are general creditors of the Company as to their own deferred compensation in, and the Company’s contributions to, the plan.