REGULATORY MATTERS, COMMITMENTS AND CONTINGENCIES - Regulatory capital positions (Detail) $ in Thousands	Sep. 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	$ 2,364,266	$ 2,433,953
Total Capital (to Risk-Weighted Assets) Actual Ratio	0.1938	0.2050
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 976,183	$ 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	$ 2,033,421	$ 2,112,630
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	0.1666	0.1780
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 549,103	$ 534,171
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.045	0.045
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,033,421	$ 2,112,630
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	0.1666	0.1780
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 732,137	$ 712,228
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.060	0.060
Leverage Ratio Actual Amount	$ 2,033,421	$ 2,112,630
Leverage Ratio Actual Ratio	0.1036	0.1014
Leverage Ratio Required For Capital Adequacy	$ 785,379	$ 833,091
Leverage Ratio Required For Capital Adequacy Ratio	0.040	0.040
FirstBank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets) Actual	$ 2,326,477	$ 2,401,390
Total Capital (to Risk-Weighted Assets) Actual Ratio	0.1907	0.2023
Total Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 975,810	$ 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	$ 1,219,762	$ 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	$ 2,073,940	$ 2,150,317
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Actual Ratio	0.1700	0.1812
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 548,893	$ 534,125
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy Ratio	0.045	0.045
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized	$ 792,845	$ 771,514
Common Equity Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	0.065	0.065
Tier 1 Capital (to Risk-Weighted Assets) Actual	$ 2,173,940	$ 2,258,317
Tier 1 Captial (to Risk-Weighted Assets) Actual Ratio	0.1782	0.1903
Tier 1 Capital (to Risk-Weighted Assets) Required For Capital Adequacy	$ 731,857	$ 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	$ 975,810	$ 949,556
Tier 1 Capital (to Risk-Weighted Assets) Required To Be Well Capitalized Ratio	0.080	0.080
Leverage Ratio Actual Amount	$ 2,173,940	$ 2,258,317
Leverage Ratio Actual Ratio	0.1108	0.1085
Leverage Ratio Required For Capital Adequacy	$ 785,053	$ 832,773
Leverage Ratio Required For Capital Adequacy Ratio	0.040	0.040
Leverage Ratio Required To Be Well Capitalized	$ 981,316	$ 1,040,967
Leverage Ratio Required To Be Well Capitalized Ratio	0.050	0.050

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 For Capital Adequacy 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
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