BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
Jun. 30, 2022
Basis of Presentation and Significant Accounting Policies [Abstract]
Principles of consolidation [Policy Text Block]	The Consolidated Financial Statements (unaudited) of First BanCorp. (the “Corporation”) have been prepared in conformity with the accounting policies stated in the Corporation’s Audited Consolidated Financial Statements for the fiscal year ended December 31, 2021 (the “audited consolidated financial statements”) included in the 2021 Annual Report on Form 10-K. Certain information and note disclosures normally included in the financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) have been condensed or omitted from these statements pursuant to the rules and regulations of the SEC and, accordingly, these financial statements should be read in conjunction with the audited consolidated financial statements, which are included in the 2021 Annual Report on Form 10-K. All adjustments (consisting only of normal recurring adjustments) that are, in the opinion of management, necessary for a fair presentation of the statement of financial position, results of operations and cash flows for the interim periods have been reflected. All significant intercompany accounts and transactions have been eliminated in consolidation.
Accounting Standards Adopted [Policy Text Block]	Adoption of New Accounting Requirements The Corporation was not impacted by the adoption of the following Accounting Standards Updates (“ASUs”) during 2022:  ASU 2021-05, “Leases (Topic 842): Lessors – Certain Leases with Variable Lease Payments”  ASU 2021-04, “Earnings Per Share (Topic 260), Debt – Modifications and Extinguishments (Subtopic 470-50), Compensation – Stock Compensation (Topic 718), and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (a Consensus of the Emerging Issues Task Force)”  ASU 2020-06, “Debt – Debt with Conversion and other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in an Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity”

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)

6 Months Ended

Jun. 30, 2022

Basis of Presentation and Significant Accounting Policies [Abstract]

Principles of consolidation [Policy Text Block]

The Consolidated Financial Statements (unaudited) of First BanCorp. (the “Corporation”) have been prepared in conformity with the accounting policies stated in the Corporation’s Audited Consolidated Financial Statements for the fiscal year ended December 31, 2021 (the “audited consolidated financial statements”) included in the 2021 Annual Report on Form 10-K. Certain information and note disclosures normally included in the financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) have been condensed or omitted from these statements pursuant to the rules and regulations of the SEC and, accordingly, these financial statements should be read in conjunction with the audited consolidated financial statements, which are included in the 2021 Annual Report on Form 10-K. All adjustments (consisting only of normal recurring adjustments) that are, in the opinion of management, necessary for a fair presentation of the statement of financial position, results of operations and cash flows for the interim periods have been reflected. All significant intercompany accounts and transactions have been eliminated in consolidation.

Accounting Standards Adopted [Policy Text Block]

Adoption of New Accounting Requirements

The Corporation was not impacted by the adoption of the following Accounting Standards Updates (“ASUs”) during 2022:

 ASU 2021-05, “Leases (Topic 842): Lessors – Certain Leases with Variable Lease Payments”

 ASU 2021-04, “Earnings Per Share (Topic 260), Debt – Modifications and Extinguishments (Subtopic 470-50), Compensation – Stock Compensation (Topic 718), and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40): Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (a Consensus of the Emerging Issues Task Force)”

 ASU 2020-06, “Debt – Debt with Conversion and other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in an Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity”