Long-Term Debt	12 Months Ended
Dec. 31, 2012
Long-term Debt, Unclassified [Abstract]
Long-Term Debt	Long-term Debt Senior Convertible Notes In November 2011, the Company issued $200.0 million aggregate principal amount of zero coupon senior convertible notes due on December 1, 2018 (the “Convertible Notes”) in a private placement offering to TCV VII, L.P., TCV VII(A), L.P., and TCV Member Fund, L.P. A general partner of these funds also serves on the Company’s Board of Directors, and as such, the issuance of the notes is considered a related party transaction. The net proceeds to the Company were approximately $197.8 million. Debt issuance costs of $2.2 million (of which $0.3 million was paid in the year ended December 31, 2012) were recorded in “Other non-current assets” on the Consolidated Balance Sheets and are amortized over the term of the notes as interest expense. The Convertible Notes are the Company’s general, unsecured obligations and are effectively subordinated to all of the Company’s existing and future secured debt, to the extent of the assets securing such debt, and are structurally subordinated to all liabilities of the Company’s subsidiaries, including trade payables. The Convertible Notes do not bear interest, except in specified circumstances. The initial conversion rate for the Convertible Notes is 11.6553 shares of the Company’s common stock, par value $0.001 per share, per $1,000 principal amount of notes. This is equivalent to an initial conversion price of approximately $85.80 per share of common stock. Holders may surrender their notes for conversion at any time prior to the close of business day immediately preceding the maturity date of the notes. The Convertible Notes are repayable in whole or in part upon the occurrence of a change of control, at the option of the holders, at a purchase price in cash equal to 120% of the principal amount. At any time following May 28, 2012, the Company may elect to cause the conversion of the Convertible Notes into shares of the Company’s common stock when specified conditions are satisfied, including that the daily volume weighted average price of the Company’s common stock is equal or greater than $111.54 for at least 50 trading days during a 65 trading day period prior to the conversion date. The Company determined that the embedded conversion option in the Convertible Notes does not require separate accounting treatment as a derivative instrument because it is both indexed to the Company’s own stock and would be classified in stockholder’s equity if freestanding. Additionally, the Convertible Notes do not require or permit any portion of the obligation to be settled in cash and accordingly the liability and equity (conversion option) components are not required to be accounted for separately. The Convertible Notes include, among other terms and conditions, limitations on the Company’s ability to pay cash dividends or to repurchase shares of its common stock, subject to specified exceptions. At December 31, 2012, the Company was in compliance with these covenants. Based on quoted market prices of the Company’s publicly traded debt (a Level 3 input for this financial instrument), the fair value of the Convertible Notes as of December 31, 2012 and 2011 was approximately $212.5 million and $206.5 million, respectively. Senior Notes In November 2009, the Company issued $200.0 million aggregate principal amount of 8.50% senior notes due November 15, 2017 (the “8.50% Notes”). The net proceeds to the Company were approximately $193.9 million. Debt issuance costs of $6.1 million were recorded in “Other non-current assets” on the Consolidated Balance Sheets and are amortized over the term of the notes as interest expense. The notes were issued at par and are senior unsecured obligations of the Company. Interest is payable semi-annually at a rate of 8.50% per annum on May 15 and November 15 of each year, commencing on May 15, 2010. The 8.50% Notes are repayable in whole or in part upon the occurrence of a change of control, at the option of the holders, at a purchase price in cash equal to 101% of the principal plus accrued interest. The Company may redeem the 8.50% Notes prior to November 15, 2013 in whole or in part at a redemption price of 100% of the principal plus accrued interest, plus a “make-whole” premium which as of December 31, 2012 would have been approximately $25 million. On or after November 15, 2013, the Company may redeem the 8.50% Notes in whole or in part at specified prices ranging from 104.25% to 100% of the principal plus accrued interest. The 8.50% Notes include, among other terms and conditions, limitations on the Company’s ability to create, incur, assume or be liable for indebtedness (other than specified types of permitted indebtedness); dispose of assets outside the ordinary course (subject to specified exceptions); acquire, merge or consolidate with or into another person or entity (other than specified types of permitted acquisitions); create, incur or allow any lien on any of its property or assign any right to receive income (except for specified permitted liens); make investments (other than specified types of investments); or pay dividends, make distributions, or purchase or redeem the Company’s equity interests (each subject to specified exceptions). At December 31, 2012 and 2011, the Company was in compliance with these covenants. Based on quoted market prices in less active markets (Level 2), the fair value of the 8.50% Notes was approximately $212.5 million and $206.5 million as of December 31, 2012 and 2011, respectively.

Long-term Debt

Senior Convertible Notes

In November 2011, the Company issued $200.0 million aggregate principal amount of zero coupon senior convertible notes due on December 1, 2018 (the “Convertible Notes”) in a private placement offering to TCV VII, L.P., TCV VII(A), L.P., and TCV Member Fund, L.P. A general partner of these funds also serves on the Company’s Board of Directors, and as such, the issuance of the notes is considered a related party transaction. The net proceeds to the Company were approximately $197.8 million. Debt issuance costs of $2.2 million (of which $0.3 million was paid in the year ended December 31, 2012) were recorded in “Other non-current assets” on the Consolidated Balance Sheets and are amortized over the term of the notes as interest expense. The Convertible Notes are the Company’s general, unsecured obligations and are effectively subordinated to all of the Company’s existing and future secured debt, to the extent of the assets securing such debt, and are structurally subordinated to all liabilities of the Company’s subsidiaries, including trade payables. The Convertible Notes do not bear interest, except in specified circumstances. The initial conversion rate for the Convertible Notes is 11.6553 shares of the Company’s common stock, par value $0.001 per share, per $1,000 principal amount of notes. This is equivalent to an initial conversion price of approximately $85.80 per share of common stock. Holders may surrender their notes for conversion at any time prior to the close of business day immediately preceding the maturity date of the notes. The Convertible Notes are repayable in whole or in part upon the occurrence of a change of control, at the option of the holders, at a purchase price in cash equal to 120% of the principal amount. At any time following May 28, 2012, the Company may elect to cause the conversion of the Convertible Notes into shares of the Company’s common stock when specified conditions are satisfied, including that the daily volume weighted average price of the Company’s common stock is equal or greater than $111.54 for at least 50 trading days during a 65 trading day period prior to the conversion date.

The Company determined that the embedded conversion option in the Convertible Notes does not require separate accounting treatment as a derivative instrument because it is both indexed to the Company’s own stock and would be classified in stockholder’s equity if freestanding. Additionally, the Convertible Notes do not require or permit any portion of the obligation to be settled in cash and accordingly the liability and equity (conversion option) components are not required to be accounted for separately.

The Convertible Notes include, among other terms and conditions, limitations on the Company’s ability to pay cash dividends or to repurchase shares of its common stock, subject to specified exceptions. At December 31, 2012, the Company was in compliance with these covenants.

Based on quoted market prices of the Company’s publicly traded debt (a Level 3 input for this financial instrument), the fair value of the Convertible Notes as of December 31, 2012 and 2011 was approximately $212.5 million and $206.5 million, respectively.

Senior Notes

In November 2009, the Company issued $200.0 million aggregate principal amount of 8.50% senior notes due November 15, 2017 (the “8.50% Notes”). The net proceeds to the Company were approximately $193.9 million. Debt issuance costs of $6.1 million were recorded in “Other non-current assets” on the Consolidated Balance Sheets and are amortized over the term of the notes as interest expense. The notes were issued at par and are senior unsecured obligations of the Company. Interest is payable semi-annually at a rate of 8.50% per annum on May 15 and November 15 of each year, commencing on May 15, 2010. The 8.50% Notes are repayable in whole or in part upon the occurrence of a change of control, at the option of the holders, at a purchase price in cash equal to 101% of the principal plus accrued interest. The Company may redeem the 8.50% Notes prior to November 15, 2013 in whole or in part at a redemption price of 100% of the principal plus accrued interest, plus a “make-whole” premium which as of December 31, 2012 would have been approximately $25 million. On or after November 15, 2013, the Company may redeem the 8.50% Notes in whole or in part at specified prices ranging from 104.25% to 100% of the principal plus accrued interest.

The 8.50% Notes include, among other terms and conditions, limitations on the Company’s ability to create, incur, assume or be liable for indebtedness (other than specified types of permitted indebtedness); dispose of assets outside the ordinary course (subject to specified exceptions); acquire, merge or consolidate with or into another person or entity (other than specified types of permitted acquisitions); create, incur or allow any lien on any of its property or assign any right to receive income (except for specified permitted liens); make investments (other than specified types of investments); or pay dividends, make distributions, or purchase or redeem the Company’s equity interests (each subject to specified exceptions). At December 31, 2012 and 2011, the Company was in compliance with these covenants.

Based on quoted market prices in less active markets (Level 2), the fair value of the 8.50% Notes was approximately $212.5 million and $206.5 million as of December 31, 2012 and 2011, respectively.