OTHER REAL ESTATE OWNED- Additional information (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Other Real Estate And Foreclosed Assets [Abstract]
Transfers From Loansto Other Receivable	$ 15,000,000	$ 8,900,000

Amount of foreclosures completed that meet the conditions of ASC 310-40 and are presented as a receivable (other assets) in the statement of financial condition.

No definition available.

Name:	fbp_TransfersFromLoanstoOtherReceivable
Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant