Subsequent Event	6 Months Ended
Jun. 30, 2011
Subsequent Event [Abstract]
Subsequent Event	17. Subsequent Events On August 3, 2011, the Company entered into a definitive merger agreement with Blackstone Capital Partners VI L.P. under which this Blackstone fund will acquire a controlling interest in the Company in a transaction valued at approximately $3 billion. H&F will maintain a significant noncontrolling equity interest in the Company. Under the terms of the merger agreement, holders of the Company's common stock will receive $19.00 per share in cash. The transaction is subject to customary closing conditions, including approval by the Company's stockholders and clearance under the Hart-Scott-Rodino Act, and is currently expected to be completed in the second half of 2011. Following completion of the proposed transaction, the Company will become a privately held company and its Class A common stock will no longer be traded on the New York Stock Exchange.

Describes disclosed significant events or transactions that occurred after the balance sheet date, but before the issuance of the financial statements. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, losses resulting from fire or flood, losses on receivables, significant realized and unrealized gains and losses that result from changes in quoted market prices of securities, declines in market prices of inventory, changes in authorized or issued debt (SEC), significant foreign exchange rate changes, substantial loans to insiders or affiliates, significant long-term investments, and substantial dividends not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 11

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