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Related Party Transactions (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2012 Diamondback Energy, Inc [Member] | Dec. 31, 2011 Diamondback Energy, Inc [Member] | Dec. 31, 2012 Windsor Niobrara LLC [Member] | Dec. 31, 2011 Windsor Niobrara LLC [Member] | Dec. 31, 2012 Windsor Ohio LLC [Member] | Dec. 31, 2011 Windsor Ohio LLC [Member] | Dec. 31, 2012 Liddell [Member] | Dec. 31, 2012 Rhino [Member] | Dec. 31, 2011 Rhino [Member] | Dec. 31, 2012 Athena [Member] | Dec. 31, 2011 Athena [Member] | Dec. 31, 2011 Directional [Member] | Dec. 31, 2012 Black Fin [Member] | Dec. 31, 2011 Black Fin [Member] | Dec. 31, 2012 Caliber [Member] | Dec. 31, 2011 Caliber [Member] | Dec. 31, 2012 Operating Lease Expense [Member] Athena [Member]
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Due from (to) related party |  |  | $ (269,000) | $ (5,593,000) | $ 173,000 | $ 3,557,000 | $ 6,520,000 | $ 0 |  | $ 4,257,000 | $ 0 | $ (1,453,000) | $ (676,000) | $ (2,449,000) | $ 0 | $ (436,000) | $ (12,000) | $ (2,000) |
Lease operating expenses |  |  | 7,089,000 | 5,489,000 |  |  |  |  |  |  |  |  | 423,000 |  |  |  |  |  | 422,000
Oil and natural gas properties |  |  | 40,354,000 | 50,614,000 |  |  |  |  |  |  |  | 5,009,000 | 2,851,000 | 6,068,000 | 650,000 | 436,000 |  |  |
Revenue from related parties |  |  |  |  | 7,545,000 | 6,642,000 | 163,650,000 | 93,871,000 | 2,020,000 | 4,443,000 | 25,862,000 |  |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |  |  |  |
Affiliates participation ratio | 50.00% | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments for ownership interest |  |  |  |  |  |  |  |  | 102,000 |  |  |  |  |  |  |  |  |  |
General and administrative |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 63,000 | $ 18,000 |

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