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Regulatory Capital Requirements - Schedule of Actual and Required Capital Ratios (Details) $ in Thousands | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Bank actual capital amount |  |
Common equity Tier 1 capital ratio | $ 2,021,589 | $ 1,022,454
Tier 1 leverage capital | 2,051,965 | 1,032,255
Risk-based capital: |  |
Tier 1 | 2,051,965 | 1,032,255
Total risk-based capital | $ 2,400,786 | $ 1,214,208
Bank actual capital ratio |  |
Common equity Tier 1 capital ratio, Actual, Ratio (as a percent) | 10.95% | 10.46%
Tier 1 leverage capital ratio (as a percent) | 0.0925 | 0.0906
Risk-based capital: |  |
Tier 1 (as a percent) | 0.1112 | 0.1056
Total (as a percent) | 0.1301 | 0.1242
Minimum capital adequacy amount |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Amount | $ 830,790 | $ 439,870
Tier 1 leverage capital | 887,336 | 455,742
Risk-based capital: |  |
Tier 1 | 1,107,175 | 586,509
Total | $ 1,476,271 | $ 782,099
Minimum capital adequacy ratio |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Ratio (as a percent) | 4.50% | 4.50%
Tier 1 leverage capital ratio (as a percent) | 0.0400 | 0.0400
Risk-based capital: |  |
Tier 1 (as a percent) | 0.0600 | 0.0600
Total (as a percent) | 0.0800 | 0.0800
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio | $ 1,292,340 | $ 684,243
Tier 1 leverage capital ratio | 887,336 | 455,742
Risk-based capital: |  |
Tier 1 risk-based capital ratio | 1,568,498 | 830,887
Total risk-based capital ratio | $ 1,937,606 | $ 1,026,504
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio (as a percent) | 7.00% | 7.00%
Tier 1 leverage capital ratio (as a percent) | 4.00% | 4.00%
Risk-based capital: |  |
Tier 1 (as a percent) | 8.50% | 8.50%
Total (as a percent) | 10.50% | 10.50%
BankRI |  |
Bank actual capital amount |  |
Common equity Tier 1 capital ratio |  | $ 294,573
Tier 1 leverage capital |  | 294,573
Risk-based capital: |  |
Tier 1 |  | 294,573
Total risk-based capital |  | $ 328,646
Bank actual capital ratio |  |
Common equity Tier 1 capital ratio, Actual, Ratio (as a percent) |  | 10.53%
Tier 1 leverage capital ratio (as a percent) |  | 0.0890
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.1053
Total (as a percent) |  | 0.1175
Minimum capital adequacy amount |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Amount |  | $ 125,886
Tier 1 leverage capital |  | 132,392
Risk-based capital: |  |
Tier 1 |  | 167,848
Total |  | $ 223,759
Minimum capital adequacy ratio |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Ratio (as a percent) |  | 4.50%
Tier 1 leverage capital ratio (as a percent) |  | 0.0400
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.0600
Total (as a percent) |  | 0.0800
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio |  | $ 195,823
Tier 1 leverage capital ratio |  | 132,392
Risk-based capital: |  |
Tier 1 risk-based capital ratio |  | 237,784
Total risk-based capital ratio |  | $ 293,684
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio (as a percent) |  | 7.00%
Tier 1 leverage capital ratio (as a percent) |  | 4.00%
Risk-based capital: |  |
Tier 1 (as a percent) |  | 8.50%
Total (as a percent) |  | 10.50%
Classified as well capitalized |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Amount |  | $ 181,835
Tier 1 leverage capital |  | 165,490
Risk-based capital: |  |
Tier 1 |  | 223,797
Total |  | $ 279,699
Classified as well capitalized ratio |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Ratio (as a percent) |  | 6.50%
Tier 1 leverage capital ratio (as a percent) |  | 0.0500
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.0800
Total (as a percent) |  | 0.1000
PCSB Bank |  |
Bank actual capital amount |  |
Common equity Tier 1 capital ratio |  | $ 197,296
Tier 1 leverage capital |  | 197,296
Risk-based capital: |  |
Tier 1 |  | 197,296
Total risk-based capital |  | $ 214,879
Bank actual capital ratio |  |
Common equity Tier 1 capital ratio, Actual, Ratio (as a percent) |  | 13.73%
Tier 1 leverage capital ratio (as a percent) |  | 0.1011
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.1373
Total (as a percent) |  | 0.1495
Minimum capital adequacy amount |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Amount |  | $ 64,664
Tier 1 leverage capital |  | 78,060
Risk-based capital: |  |
Tier 1 |  | 86,218
Total |  | $ 114,985
Minimum capital adequacy ratio |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Ratio (as a percent) |  | 4.50%
Tier 1 leverage capital ratio (as a percent) |  | 0.0400
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.0600
Total (as a percent) |  | 0.0800
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio |  | $ 100,588
Tier 1 leverage capital ratio |  | 78,060
Risk-based capital: |  |
Tier 1 risk-based capital ratio |  | 122,142
Total risk-based capital ratio |  | $ 150,918
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio (as a percent) |  | 7.00%
Tier 1 leverage capital ratio (as a percent) |  | 4.00%
Risk-based capital: |  |
Tier 1 (as a percent) |  | 8.50%
Total (as a percent) |  | 10.50%
Classified as well capitalized |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Amount |  | $ 93,403
Tier 1 leverage capital |  | 97,575
Risk-based capital: |  |
Tier 1 |  | 114,958
Total |  | $ 143,732
Classified as well capitalized ratio |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Ratio (as a percent) |  | 6.50%
Tier 1 leverage capital ratio (as a percent) |  | 0.0500
Risk-based capital: |  |
Tier 1 (as a percent) |  | 0.0800
Total (as a percent) |  | 0.1000
Beacon Bank & Trust |  |
Bank actual capital amount |  |
Common equity Tier 1 capital ratio | $ 2,069,767 | $ 584,420
Tier 1 leverage capital | 2,069,767 | 584,420
Risk-based capital: |  |
Tier 1 | 2,069,767 | 584,420
Total risk-based capital | $ 2,280,038 | $ 654,287
Bank actual capital ratio |  |
Common equity Tier 1 capital ratio, Actual, Ratio (as a percent) | 11.22% | 10.47%
Tier 1 leverage capital ratio (as a percent) | 0.0939 | 0.0930
Risk-based capital: |  |
Tier 1 (as a percent) | 0.1122 | 0.1047
Total (as a percent) | 0.1236 | 0.1173
Minimum capital adequacy amount |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Amount | $ 830,120 | $ 251,183
Tier 1 leverage capital | 881,690 | 251,363
Risk-based capital: |  |
Tier 1 | 1,106,827 | 334,911
Total | $ 1,475,753 | $ 446,232
Minimum capital adequacy ratio |  |
Common equity Tier 1 capital ratio, Minimum Required for Capital Adequacy Purposes, Ratio (as a percent) | 4.50% | 4.50%
Tier 1 leverage capital ratio (as a percent) | 0.0400 | 0.0400
Risk-based capital: |  |
Tier 1 (as a percent) | 0.0600 | 0.0600
Total (as a percent) | 0.0800 | 0.0800
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio | $ 1,291,298 | $ 390,730
Tier 1 leverage capital ratio | 881,690 | 251,363
Risk-based capital: |  |
Tier 1 risk-based capital ratio | 1,568,005 | 474,457
Total risk-based capital ratio | $ 1,936,925 | $ 585,679
Minimum Required for Fully Phased in Capital Adequacy Purposes plus Capital Conservation Buffer |  |
Common equity Tier 1 capital ratio (as a percent) | 7.00% | 7.00%
Tier 1 leverage capital ratio (as a percent) | 4.00% | 4.00%
Risk-based capital: |  |
Tier 1 (as a percent) | 8.50% | 8.50%
Total (as a percent) | 10.50% | 10.50%
Classified as well capitalized |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Amount | $ 1,199,063 | $ 362,820
Tier 1 leverage capital | 1,102,112 | 314,204
Risk-based capital: |  |
Tier 1 | 1,475,770 | 446,548
Total | $ 1,844,691 | $ 557,789
Classified as well capitalized ratio |  |
Common equity Tier 1 capital ratio, Minimum Required to be Considered Well-Capitalized, Ratio (as a percent) | 6.50% | 6.50%
Tier 1 leverage capital ratio (as a percent) | 0.0500 | 0.0500
Risk-based capital: |  |
Tier 1 (as a percent) | 0.080 | 0.0800
Total (as a percent) | 0.1000 | 0.1000

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