CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred Stock, shares authorized	50,000,000us-gaap_PreferredStockSharesAuthorized	50,000,000us-gaap_PreferredStockSharesAuthorized
Preferred Stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred Stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Class A Common Stock
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, authorized shares	500,000,000	500,000,000
Common Stock, issued shares	102,558,529	102,392,208
Common Stock, outstanding shares	102,558,529	102,392,208
Class B Non-Voting Common Stock
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, authorized shares	10,000,000	10,000,000
Common Stock, issued shares	0	0
Common Stock, outstanding shares	0	0

Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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