Fair Value	6 Months Ended	12 Months Ended
Fair Value	Jun. 30, 2013	Dec. 31, 2012
Fair Value
Fair Value	5. Fair Value Financial instruments include cash and cash equivalents, notes payable and long-term debt. The carrying amount of cash and cash equivalents approximates fair value because of the short-term maturity of these instruments. The carrying value of the Company's senior secured credit facility was $1,226.6 million and $916.1 million at December 31, 2012 and June 30, 2013, respectively. The fair value of the Company's senior secured credit facility was $1,216.2 million and $907.8 million at December 31, 2012 and June 30, 2013, respectively. The fair value of the Company's senior secured credit facility was based on quoted market prices for this debt in the syndicated loan market. The carrying value of the Company's 6.375% senior notes was $600.0 million at June 30, 2013. The fair value of the Company's 6.375% senior notes was $570.0 million June 30, 2013. The fair value of this debt was based on quoted market prices. The Company considers the inputs in the valuation process of its senior secured credit facility and 6.375% senior notes to be Level 2 in the fair value hierarchy. Level 2 in the fair value hierarchy is defined as inputs that are observable for the asset or liability, either directly or indirectly which includes quoted prices for identical assets or liabilities in markets that are not active.	11. Fair Value Financial instruments include cash and cash equivalents, notes payable and long-term debt. The carrying amount of cash and cash equivalents approximates fair value because of the short-term maturity of these instruments. The carrying value of the Company's senior secured credit facility was $878.0 million and $1,226.6 million at December 31, 2011 and December 31, 2012, respectively. The fair value of the Company's senior secured credit facility was $823.3 million and $1,216.2 million at December 31, 2011 and 2012, respectively. The fair value of the Company's senior secured credit facility was based on quoted market prices for this debt in the syndicated loan market. The carrying value of the Company's 7⁵/8% senior subordinated notes was $345.0 million and $70.0 million at December 31, 2011 and December 31, 2012, respectively. The fair value of the Company's 7⁵/8% senior subordinated notes was $326.4 million and $70.8 million at December 31, 2011 and December 31, 2012, respectively. The fair value of this registered debt was based on quoted market prices. The Company considers the inputs in the valuation process of its debt instruments to be Level 2 in the fair value hierarchy due to the Company's 7⁵/8% senior subordinated notes being thinly traded.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

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