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Stock - Based Compensation - Summary of Accumulated Stock Units (Detail) (USD $) | Dec. 31, 2014 | Dec. 31, 2013
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Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |  |
Accumulated stock units | 60,859 banf_DeferredCompensationArrangementWithIndividualAccumulatedStockUnitsForDeferredBoardFees | 56,380 banf_DeferredCompensationArrangementWithIndividualAccumulatedStockUnitsForDeferredBoardFees
Average price | $ 37.41 banf_DeferredCompensationArrangementWithIndividualStockAveragePrice | $ 35.31 banf_DeferredCompensationArrangementWithIndividualStockAveragePrice

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- Definition Deferred compensation arrangement with individual accumulated stock units For deferred board fees. + References No definition available. + Details
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- Definition Deferred compensation arrangement with individual stock average price. + References No definition available. + Details
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- Details
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