Debt	9 Months Ended
Sep. 30, 2011
Debt Disclosure [Abstract]
Debt	Debt The Company's debt agreements contain financial covenants that require the maintenance of interest coverage and leverage ratios. The Company is in compliance with its debt covenants as of September 30, 2011, and closely monitors its future compliance based on current and anticipated future economic conditions. On September 27, 2011, the Company entered into an amended and restated revolving credit agreement (the “Amended Credit Agreement”) with Bank of America, N.A. as the administrative agent. The Amended Credit Agreement increases the borrowing availability of the debt facility from $400,000 to $500,000. The Amended Credit Agreement also extends the expiration date of the debt facility by four years from September 2012 to September 2016. At September 30, 2011, borrowings and availability under the Amended Credit Agreement were $286,100 and $213,900, respectively. Borrowings under the Amended Credit Agreement bear interest at LIBOR plus a spread ranging from 1.10% to 1.70%, depending on the Company's leverage ratio at the time of the borrowing. As with the prior revolving credit agreement, the Company's borrowing capacity is limited by various debt covenants within the Amended Credit Agreement. The Amended Credit Agreement requires the Company to maintain a ratio of Consolidated Senior Debt, as defined in the Amended Credit Agreement, to Consolidated EBITDA, as defined in the Amended Credit Agreement, of not more than 3.25 times at the end of each fiscal quarter ending on or before September 30, 2013, after which the ratio will decrease to 3.00 times. In addition, the Amended Credit Agreement requires the Company to maintain a ratio of Consolidated Total Debt, as defined in the Amended Credit Agreement, to Consolidated EBITDA of not more than 4.00 times for each fiscal quarter ending on or before September 30, 2013, and thereafter of not more than 3.75 times at the end of any fiscal quarter, and a ratio of Consolidated EBITDA to Consolidated Cash Interest Expense, as defined in the Amended Credit Agreement, of not less than 4.25 times for each fiscal quarter ending on or before September 30, 2013, and thereafter of not less than 4.50 times at the end of any fiscal quarter. At September 30, 2011, the Company was in compliance with all covenants under the Amended Credit Agreement. The Company paid fees and expenses of $1,927 in conjunction with the refinancing of the Amended Credit Agreement; such fees will be deferred and amortized into interest expense on the accompanying Consolidated Statements of Income through its maturity. Effective April 5, 2011, the Company exercised its right to redeem the remaining $92,500 principal amount of the 3.75% Convertible Notes under their indenture agreement. Of the total $92,500 principal amount, $11,865 of these notes were redeemed with accrued interest through the redemption date. The remaining $80,635 of these notes were surrendered for conversion. The Company elected to pay cash to holders of the notes surrendered for conversion, including the value of any residual shares of common stock that were payable to the holders electing to convert their notes into an equivalent share value, resulting in a total cash payment of $90,438 including a premium on conversion of $9,803 which reduced the equity component by $6,085, net of tax of $3,718. As a result of this transaction, the Company recaptured $40,217 of previously deducted contingent convertible debt interest which resulted in a $15,252 reduction in short-term deferred tax liabilities as well as a reduction of tax loss carryforwards reflected in long-term deferred tax assets. The Company used borrowings under its senior credit facility to finance the redemption of the 3.75% Convertible Notes. The 3.375% Convertible Notes are subject to redemption at their par value at any time, at the option of the Company, on or after March 20, 2014. The note holders may also require the Company to redeem some or all of the notes at their par value on March 15^th of 2014, 2017 and 2022. The 3.375% Convertible Notes are also eligible for conversion upon meeting certain conditions as provided in the indenture agreement. The eligibility for conversion is determined quarterly. During the third quarter of 2011, the 3.375% Convertible Notes were not eligible for conversion. During the fourth quarter of 2011, the 3.375% Convertible Notes will not be eligible for conversion.

Debt

The Company's debt agreements contain financial covenants that require the maintenance of interest coverage and leverage ratios. The Company is in compliance with its debt covenants as of September 30, 2011, and closely monitors its future compliance based on current and anticipated future economic conditions.

On September 27, 2011, the Company entered into an amended and restated revolving credit agreement (the “Amended Credit Agreement”) with Bank of America, N.A. as the administrative agent. The Amended Credit Agreement increases the borrowing availability of the debt facility from $400,000 to $500,000. The Amended Credit Agreement also extends the expiration date of the debt facility by four years from September 2012 to September 2016. At September 30, 2011, borrowings and availability under the Amended Credit Agreement were $286,100 and $213,900, respectively. Borrowings under the Amended Credit Agreement bear interest at LIBOR plus a spread ranging from 1.10% to 1.70%, depending on the Company's leverage ratio at the time of the borrowing.

As with the prior revolving credit agreement, the Company's borrowing capacity is limited by various debt covenants within the Amended Credit Agreement. The Amended Credit Agreement requires the Company to maintain a ratio of Consolidated Senior Debt, as defined in the Amended Credit Agreement, to Consolidated EBITDA, as defined in the Amended Credit Agreement, of not more than 3.25 times at the end of each fiscal quarter ending on or before September 30, 2013, after which the ratio will decrease to 3.00 times. In addition, the Amended Credit Agreement requires the Company to maintain a ratio of Consolidated Total Debt, as defined in the Amended Credit Agreement, to Consolidated EBITDA of not more than 4.00 times for each fiscal quarter ending on or before September 30, 2013, and thereafter of not more than 3.75 times at the end of any fiscal quarter, and a ratio of Consolidated EBITDA to Consolidated Cash Interest Expense, as defined in the Amended Credit Agreement, of not less than 4.25 times for each fiscal quarter ending on or before September 30, 2013, and thereafter of not less than 4.50 times at the end of any fiscal quarter. At September 30, 2011, the Company was in compliance with all covenants under the Amended Credit Agreement. The Company paid fees and expenses of $1,927 in conjunction with the refinancing of the Amended Credit Agreement; such fees will be deferred and amortized into interest expense on the accompanying Consolidated Statements of Income through its maturity.

Effective April 5, 2011, the Company exercised its right to redeem the remaining $92,500 principal amount of the 3.75% Convertible Notes under their indenture agreement. Of the total $92,500 principal amount, $11,865 of these notes were redeemed with accrued interest through the redemption date. The remaining $80,635 of these notes were surrendered for conversion. The Company elected to pay cash to holders of the notes surrendered for conversion, including the value of any residual shares of common stock that were payable to the holders electing to convert their notes into an equivalent share value, resulting in a total cash payment of $90,438 including a premium on conversion of $9,803 which reduced the equity component by $6,085, net of tax of $3,718. As a result of this transaction, the Company recaptured $40,217 of previously deducted contingent convertible debt interest which resulted in a $15,252 reduction in short-term deferred tax liabilities as well as a reduction of tax loss carryforwards reflected in long-term deferred tax assets. The Company used borrowings under its senior credit facility to finance the redemption of the 3.75% Convertible Notes.

The 3.375% Convertible Notes are subject to redemption at their par value at any time, at the option of the Company, on or after March 20, 2014. The note holders may also require the Company to redeem some or all of the notes at their par value on March 15^th of 2014, 2017 and 2022. The 3.375% Convertible Notes are also eligible for conversion upon meeting certain conditions as provided in the indenture agreement. The eligibility for conversion is determined quarterly. During the third quarter of 2011, the 3.375% Convertible Notes were not eligible for conversion. During the fourth quarter of 2011, the 3.375% Convertible Notes will not be eligible for conversion.