Recent Developments Including Mergers and Acquisitions	3 Months Ended
Mar. 31, 2013
Recent Developments Including Mergers and Acquisitions [Abstract]
RECENT DEVELOPMENTS, INCLUDING MERGERS AND ACQUISITIONS	(2) RECENT DEVELOPMENTS, INCLUDING MERGERS AND ACQUISITIONS On January 19, 2012, Council Oak Investment Corporation, a wholly-owned subsidiary of BancFirst, completed the sale of one of its investments that resulted in a pretax gain of approximately $4.5 million. After related expenses and income taxes, the increase in net income approximated $2.6 million. The gain was included in first quarter 2012 earnings.

Recent developments including mergers and acquisitions.

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