Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Common stock, shares outstanding	75,345,023us-gaap_CommonStockSharesOutstanding
General Partners' Capital Account, Units Outstanding	75,345,023
Limited Partners' Capital Account, Units Outstanding	4,189,966
Parent Company [Member]
Common stock, par value per share	0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	75,345,023	75,267,675
Common stock, shares outstanding	75,345,023	75,267,675
Limited Partner [Member]
General Partners' Capital Account, Units Outstanding	75,345,023	75,267,675
Limited Partners' Capital Account, Units Outstanding	4,189,966	4,191,152

Face amount or stated value per share of common stock.

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The number of limited partner units outstanding.

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