Current report filing

Consolidated Balance Sheets (Parenthetical)

v2.4.0.8
Consolidated Balance Sheets (Parenthetical) (USD $)
3 Months Ended 12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Dec. 31, 2012
Dec. 31, 2011
Statement of Financial Position [Abstract]        
Capitalized costs of oil and natural gas properties excluded from amortization $ 869,879,000 $ 626,295,000 $ 626,295,000 $ 138,623,000
Preferred stock, par value (usd per share) $ 0.01 $ 0.01 $ 0.01 $ 0.01
Preferred stock, shares authorized (shares) 5,000,000 5,000,000 5,000,000 5,000,000
Preferred stock dividend rate 12.00% 12.00% 12.00% 12.00%
Temporary Equity, Shares Authorized (shares) 30,000 30,000 30,000 30,000
Preferred stock Series A, issued (shares) 0 0 0 0
Preferred stock Series A, outstanding (shares) 0 0 0 0
Common stock, par value (usd per share) $ 0.01 $ 0.01 $ 0.01 $ 0.01
Common Stock, Shares Authorized (shares) 100,000,000 100,000,000 100,000,000 100,000,000
Common Stock, Shares, Issued (shares) 77,375,107 67,527,386 67,527,386 55,621,371
Common Stock, Shares, Outstanding (shares) 77,375,107 67,527,386 67,527,386 55,621,371
Equity investments attributable to fair value option $ 212,413,000 $ 151,317,000 $ 151,317,000 $ 0