Impact of new accounting Principle in crdit loss liability of off-balanse sheet commitment.

No definition available.

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Namespace Prefix:	fbp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118956080&loc=d3e11927-110247

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82919202-210446

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

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ALLOWANCE FOR CREDIT LOSSES ON LOANS AND FINANCE LOSSES - Activity in ACL for unfunded loan commitments and standby letters of credit (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Apr. 01, 2020	Jan. 01, 2020	Apr. 01, 2019	Jan. 01, 2019
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 7,084	$ 0	$ 0	$ 412
Provision (release) for credit losses	(803)	0	2,359	(412)
Ending Balance	$ 6,281	$ 0	$ 6,281	$ 0
ASC 326 \| Cumulative Effect Period Of Adoption Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impact of adopting ASC 326 on unfunded loan commitments and standby letters of credit					$ 0	$ 3,922	$ 0	$ 0