ALLOWANCE FOR LOAN AND LEASE LOSSES - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended
May 31, 2014	Mar. 31, 2015
Financing Receivable Allowance For Credit Losses [Line Items]
Reserve for unfunded loan commitments		$ 0.5fbp_ReserveForUnfundedLoanCommitments
Changes In Allowance For Loan Losses	$ (4.8)fbp_ChangesInAllowanceForLoanLosses

Amount of increase (decrease) in Allowance for Loan Losses. The allowance is a valuation for the amount expected to be needed to absorb any estimated credit losses inherent on a given loan and lease portfolio. Includes effect from the enhancements performed to the allowance estimation process during the year.

No definition available.

Name:	fbp_ChangesInAllowanceForLoanLosses
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration