REGULATORY MATTERS, COMMITMENTS, AND CONTINGENCIES - Regulatory capital positions (Detail) $ in Thousands	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
First BanCorp [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,366,591	$ 2,385,866
Total Capital (to Risk-Weighted Assets) Actual Ratio	19.02	19.21
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 995,597	$ 993,405
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	8.0	8.0
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,032,369	$ 2,052,333
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	16.33	16.53
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 560,023	$ 558,790
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	4.5	4.5
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,032,369	$ 2,052,333
Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	16.33	16.53
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 746,697	$ 745,054
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	6.0	6.0
Leverage Ratio Actual Amount	$ 2,032,369	$ 2,052,333
Leverage Ratio Actual Ratio	10.57	10.70
Leverage Ratio Required For Capital Adequacy	$ 769,399	$ 767,075
Leverage Ratio Required For Capital Adequacy Ratio	4.0	4.0
FirstBank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,327,600	$ 2,346,093
Total Capital (to Risk-Weighted Assets) Actual Ratio	18.71	18.90
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 995,452	$ 993,264
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	8.0	8.0
Total Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 1,244,315	$ 1,241,580
Total Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	10.0	10.0
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,071,650	$ 2,090,832
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	16.65	16.84
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 559,942	$ 558,711
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	4.5	4.5
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 808,805	$ 807,027
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	6.5	6.5
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,171,650	$ 2,190,832
Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	17.45	17.65
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 746,589	$ 744,948
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	6.0	6.0
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 995,452	$ 993,264
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	8.0	8.0
Leverage Ratio Actual Amount	$ 2,171,650	$ 2,190,832
Leverage Ratio Actual Ratio	11.29	11.43
Leverage Ratio Required For Capital Adequacy	$ 769,102	$ 766,714
Leverage Ratio Required For Capital Adequacy Ratio	4.0	4.0
Leverage Ratio Required To Be Well Capitalized	$ 961,378	$ 958,392
Leverage Ratio Required To Be Well Capitalized Ratio	5.0	5.0

Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio

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Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
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