Consolidated Statements of Financial Condition (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loans receivable, net of allowance for loan losses	$ 1,179	$ 1,206
Preferred stock, par value	$ 0us-gaap_PreferredStockNoParValue	$ 0us-gaap_PreferredStockNoParValue
Preferred stock, shares authorized	1,000,000us-gaap_PreferredStockSharesAuthorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	20,000,000us-gaap_CommonStockSharesAuthorized	20,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	696,339us-gaap_CommonStockSharesIssued	694,574us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	696,339us-gaap_CommonStockSharesOutstanding	694,574us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	0us-gaap_TreasuryStockShares	24,318us-gaap_TreasuryStockShares
Share conversion ratio		0.3562bffi_ConversionOfferingExchangeRatio
Common Stock [Member]
Share conversion ratio	0.3562	0.3562
Treasury Stock [Member]
Share conversion ratio		0.3562

Conversion offering exchange ratio.

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Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Face amount per share of no-par value preferred stock nonredeemable or redeemable solely at the option of the issuer.

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