Share Repurchases	3 Months Ended
Mar. 31, 2012
Share Repurchases [Abstract]
Share Repurchases	13. Share Repurchases In October 2011, the Board of Directors authorized a share repurchase program for up to $35.0 million of the Company’s common stock. As of March 31, 2012, the Company repurchased 820,894 shares of common stock at a cost of $25.2 million. Shares repurchased under the program will be held in treasury for future use. On February 28, 2012, the Company repurchased 1,821,730 shares of the Company’s non-voting common stock from the Stockholder Broker-Dealer Client at a cost of $52.9 million. Shares repurchased from the Stockholder Broker-Dealer Client were cancelled by the Company.

The entire disclosure for an entity's treasury stock, including the average cost per share, carrying basis for each class of treasury stock, description of share repurchase program authorized by an entity's board of directors, the number of shares repurchased, the cost of the shares repurchased, the remaining maximum dollar value of shares available for repurchase under the program, the treatment of the purchase price in excess of the current market value, number of shares held for each class of treasury stock, and other information necessary to a fair presentation.

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