REGULATORY MATTERS, COMMITMENTS AND CONTINGENCIES - Regulatory capital positions (Detail) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
First BanCorp [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,378,124	$ 2,433,953
Total Capital (to Risk-Weighted Assets) Actual Ratio	0.1967	0.2050
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 966,978	$ 949,637
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.080	0.080
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,049,120	$ 2,112,630
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	0.1695	0.1780
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy	$ 543,925	$ 534,171
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy Ratio	0.045	0.045
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,049,120	$ 2,112,630
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	0.1695	0.1780
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 725,234	$ 712,228
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.060	0.060
Leverage Ratio Actual Amount	$ 2,049,120	$ 2,112,630
Leverage Ratio Actual Ratio	0.1018	0.1014
Leverage Ratio Required For Captial Adequacy	$ 805,294	$ 833,091
Leverage Ratio Required For Capital Adequancy Ratio	0.040	0.040
FirstBank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,290,652	$ 2,401,390
Total Capital (to Risk-Weighted Assets) Actual Ratio	0.1896	0.2023
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 966,755	$ 949,556
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.080	0.080
Total Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 1,208,444	$ 1,186,944
Total Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	0.100	0.100
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,039,899	$ 2,150,317
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	0.1688	0.1812
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy	$ 543,800	$ 534,125
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy Ratio	0.045	0.045
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 785,488	$ 771,514
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	0.065	0.065
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,139,899	$ 2,258,317
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	0.1771	0.1903
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 725,066	$ 712,167
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.060	0.060
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 966,755	$ 949,556
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	0.080	0.080
Leverage Ratio Actual Amount	$ 2,139,899	$ 2,258,317
Leverage Ratio Actual Ratio	0.1063	0.1085
Leverage Ratio Required For Captial Adequacy	$ 804,971	$ 832,773
Leverage Ratio Required For Capital Adequancy Ratio	0.040	0.040
Leverage Ratio Required To Be Well Capitalized	$ 1,006,214	$ 1,040,967
Leverage Ratio Required To Be Well Capitalized Ratio	0.050	0.050

Common Equity Tier 1 capital divided by risk weighted assets as defined by new Basel III rule.

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Common Equity Tier 1 Captial (to Risk-Weighted Assets) Ratio, Required For Captial Adequacy

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Minimun common equity tier 1 capital to risk weight assets ratio for well capitalized purposes plus capital conservation buffer as required by Basel III rule.

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
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-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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Amount of Common Equity Tier 1 risk-based capital as defined by regulatory framework.

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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.

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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