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Subsequent Events | 12 Months Ended
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Dec. 31, 2011
Subsequent Events [Abstract] |
Subsequent Events | 15. Subsequent Events Volume Commitment Agreements — In January 2012, the Company entered into a volume commitment agreement with a requirement to deliver a minimum quantity of approximately 4.4 MMBbl from its Williston Basin project areas within a specified timeframe. The future obligation under this agreement is approximately $13.0 million. Derivative Instruments — In February 2012, the Company converted its deferred premium put contracts for 1,000 barrels of oil per day in the remaining calendar year 2012 (beginning in March 2012) to three-way costless collar options by selling a call at $111.30 per barrel. These derivative instruments do not qualify for and were not designated as hedging instruments for accounting purposes.

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- Definition The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business. + References No definition available. + Details
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