BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 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, except for the change in accounting method for accounting for its treasury stock discussed below. 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.
Recently Issued Accounting Standards Not Yet Effective or Not Yet 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” Recently Issued Accounting Standards Not Yet Effective or Not Yet Adopted Standard Description Effective Date Effect on the financial statements ASU 2022-03, “Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions” In June 2022, the Financial Accounting Standards Board (“FASB”) issued ASU 2022 -03 which, among other things, clarifies that a contractual restriction on the sale of an equity security is not considered part of the unit of account and, therefore, is not considered in measuring fair value; and introduces new disclosure requirements for equity securities subject to contractual sale restrictions. January 1, 2024. Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance. The Corporation is evaluating the impact that this ASU will have on its financial statements and disclosures. The Corporation does not expect to be materially impacted by the adoption of this ASU during the first quarter of 2024. ASU 2022-02, “Financial Instruments – Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures” In March 2022, the FASB issued ASU 2022-02 which eliminates the troubled debt restructurings (“TDRs”) recognition and measurement guidance, enhances disclosure requirements for loan restructurings by creditors made to borrowers experiencing financial difficulty for which the terms of the receivables have been modified, and amends the guidance on vintage disclosures to require disclosure of gross write-offs by year of origination. January 1, 2023, unless early adopted in which case the amendments should be applied as of the beginning of the fiscal year that includes the interim period The Corporation is evaluating the impact that this ASU will have on its financial statements and disclosures. The Corporation expects to adopt the amendments of this update during the first quarter of 2023 using a modified retrospective transition method to account for any adjustments to the ACL that had been calculated using a discounted cash flow methodology for loans modified as a TDR prior to the adoption of these amendments. As of September 30, 2022, the Corporation expects that the adoption of this ASU will result in a cumulative effect adjustment to retained earnings, at the adoption date, in a range of $ 1 million to $ 2 million, after-tax. ASU 2022-01, “Derivatives and Hedging (Topic 815): Fair Value Hedging – Portfolio Layer Method” In March 2022, the FASB issued ASU 2022-01 which, among others, expands the current last-of-layer method to allow multiple hedged layers and the scope of the portfolio layer method to non-prepayable financial assets. January 1, 2023, unless early adopted in which case the amendments should be applied as of the beginning of the fiscal year that includes the interim period The Corporation does not expect to be impacted by the amendments of this update since it does not apply fair value hedge accounting to any of its derivatives.