Income Taxes (Scheule of Deferred Tax Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Allowance for loan losses	$ 14,558	$ 18,459
Excess book over tax SERP retirement plan cost	2,566	2,572
Deferred compensation	78	94
Federal & state net operating loss carryforwards	1,066	10,901
Accruals, book versus tax	1,779	1,604
Pension liability adjustments	100
Foreclosed real estate	1,222	2,781
Nonqualified stock options	521	522
Deferred Tax Assets, Investments	219us-gaap_DeferredTaxAssetsInvestments	237us-gaap_DeferredTaxAssetsInvestments
Unrealized gain on securities available for sale	270	789
All other	212us-gaap_DeferredTaxAssetsOther	618us-gaap_DeferredTaxAssetsOther
Gross deferred tax assets	22,591us-gaap_DeferredTaxAssetsGross	38,577us-gaap_DeferredTaxAssetsGross
Less: Valuation allowance	(125)	(109)
Net deferred tax assets	22,466us-gaap_DeferredTaxAssetsNet	38,468us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Loan fees	(1,413)fbp_LoanFees	(1,536)fbp_LoanFees
Excess tax over book pension cost	(1,316)	(806)
Depreciable basis of fixed assets	(1,197)	(1,835)
Amortizable basis of intangible assets	(10,582)	(9,732)
Pension liability adjustments		(2,003)
FHLB stock dividends	(422)fbp_FhlbStockDividends	(423)fbp_FhlbStockDividends
Basis differences in assets acquired in FDIC transactions	(2,322)	(7,163)
All other	(23)us-gaap_DeferredTaxLiabilitiesOther	(48)us-gaap_DeferredTaxLiabilitiesOther
Gross deferred tax liabilities	(17,275)us-gaap_DeferredIncomeTaxLiabilities	(23,546)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset (liability) - included in other assets	$ 5,191us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 14,922us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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