REGULATORY MATTERS, COMMITMENTS, AND CONTINGENCIES - Regulatory capital positions (Detail) $ in Thousands	Dec. 31, 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	$ 2,385,866	$ 2,433,953
Total Capital (to Risk-Weighted Assets) Actual Ratio	19.21	20.50
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 993,405	$ 949,637
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	$ 2,052,333	$ 2,112,630
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	16.53	17.80
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy	$ 558,790	$ 534,171
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy Ratio	4.5	4.5
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,052,333	$ 2,112,630
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	16.53	17.80
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 745,054	$ 712,228
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	6.0	6.0
Leverage Ratio Actual Amount	$ 2,052,333	$ 2,112,630
Leverage Ratio Actual Ratio	10.70	10.14
Leverage Ratio Required For Captial Adequacy	$ 767,075	$ 833,091
Leverage Ratio Required For Capital Adequancy Ratio	4.0	4.0
FirstBank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,346,093	$ 2,401,390
Total Capital (to Risk-Weighted Assets) Actual Ratio	18.90	20.23
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 993,264	$ 949,556
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	$ 1,241,580	$ 1,186,944
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	$ 2,090,832	$ 2,150,317
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	16.84	18.12
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy	$ 558,711	$ 534,125
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required For Captial Adequacy Ratio	4.5	4.5
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 807,027	$ 771,514
Common Equity Tier 1 Captial (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	6.5	6.5
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,190,832	$ 2,258,317
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	17.65	19.03
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 744,948	$ 712,167
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	$ 993,264	$ 949,556
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	8.0	8.0
Leverage Ratio Actual Amount	$ 2,190,832	$ 2,258,317
Leverage Ratio Actual Ratio	11.43	10.85
Leverage Ratio Required For Captial Adequacy	$ 766,714	$ 832,773
Leverage Ratio Required For Capital Adequancy Ratio	4.0	4.0
Leverage Ratio Required To Be Well Capitalized	$ 958,392	$ 1,040,967
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 Captial (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
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