Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Treasury stock, shares	30,967us-gaap_TreasuryStockShares	1,306,177us-gaap_TreasuryStockShares
Class A
Common stock, par value	0.01	0.01
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	73,373,744	66,958,867
Common stock, shares outstanding	73,342,777	65,652,690

Face amount or stated value per share of common stock.

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