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v3.23.2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 15, 2021 USD ($) $ / shares shares | Jun. 30, 2023 USD ($) shares | Jun. 30, 2023 USD ($) segment shares | Jun. 30, 2022 USD ($) shares | Mar. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares | Mar. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Stock price per share (in usd per share) | $ / shares | $ 10 |  |  |  |  |  |  |
Gross offering proceeds | $ 277,700 |  |  |  |  |  |  |
Charitable contribution in cash | $ 1,500 |  |  |  |  |  |  |
Shares in ESOP (in shares) | shares | 2,281,800 | 2,281,800 | 2,281,800 |  |  |  |  |
Loans receivable, allowance |  | $ 14,413 | $ 14,413 | $ 14,050 | $ 14,153 | $ 13,400 | $ 13,465 | $ 14,425
Reversal in reserve for commitments and letters of credit |  | 636 | $ 636 |  |  | 1,700 |  |
Number of operating segments | segment |  |  | 1 |  |  |  |  |
Shareholders' equity |  | $ (366,534) | $ (366,534) | $ (412,293) | (385,693) | $ (393,718) | (420,214) | (429,471)
ESOP shares committed to be released (in shares) | shares |  | 22,818 | 45,636 | 22,818 |  |  |  |
Common stock, outstanding (in shares) | shares |  | 25,493,422 | 25,493,422 |  |  | 27,523,219 |  |
Unallocated Common Stock Held by ESOP |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | $ 20,536 | $ 20,536 | $ 21,449 | 20,764 | $ 20,993 | 21,677 | 21,905
Retained Earnings |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | (168,703) | (168,703) | (170,050) | (170,528) | (171,763) | (170,010) | (169,457)
Common Stock |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | $ (285) | $ (285) | $ (285) | $ (285) | $ (285) | $ (285) | $ (285)
Common stock, outstanding (in shares) | shares |  | 25,493,422 | 25,493,422 | 28,522,500 | 27,385,482 | 27,523,219 | 28,522,500 | 28,522,500
Additional Paid-In Capital |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | $ (272,267) | $ (272,267) | $ (282,154) | $ (271,507) | $ (279,454) | $ (282,100) | $ (282,006)
Treasury Stock |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | 31,060 | 31,060 | 0 | 12,737 | 12,072 | 0 | 0
Accumulated Other Comprehensive Income (Loss) |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  | $ 23,125 | $ 23,125 | $ 18,747 | 23,126 | 24,719 | 10,504 | 372
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | 18 |  |
Loans receivable, allowance |  |  |  |  | $ 0 | 668 | $ 0 | $ 0
Held-to-maturities securities allowance |  |  |  |  |  | 170 |  |
Reversal in reserve for commitments and letters of credit |  |  |  |  |  | (811) |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 8 |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2022-02 | Unallocated Common Stock Held by ESOP |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Loans receivable, allowance |  |  |  |  |  | 660 |  |
Shareholders' equity |  |  |  |  |  | 18 |  |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2016-13 | Unallocated Common Stock Held by ESOP |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 8 |  |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 18 |  |
Cumulative Effect, Period of Adoption, Adjustment | Common Stock | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | $ 0 |  |
Common stock, outstanding (in shares) | shares |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Common Stock | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | $ 0 |  |
Common stock, outstanding (in shares) | shares |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Additional Paid-In Capital | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | $ 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Additional Paid-In Capital | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Treasury Stock | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Treasury Stock | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2022-02 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 0 |  |
Cumulative Effect, Period of Adoption, Adjustment | Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | $ 0 |  |
Public stock offering |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shares of common stock sold (in shares) | shares | 27,772,500 |  |  |  |  |  |  |
Donation of shares to Blue Foundry Charitable Foundation |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Shares of common stock sold (in shares) | shares | 750,000 |  |  |  |  |  |  |
Blue Foundry Bancorp - NJ |  |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |  |
Ownership interest percentage |  | 100.00% | 100.00% |  |  |  |  |

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