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SHAREHOLDERS' EQUITY - Regulatory Capital Requirements (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
The Company |  |
Common Equity Tier 1 risk-based capital ratio: |  |
Actual capital | $ 2,202,901 | $ 2,153,721
Actual ratio | 11.77% | 11.31%
Capital adequacy guidelines ratio | 4.50% | 4.50%
Tier 1 risk-based capital ratio: |  |
Actual capital | $ 2,502,901 | $ 2,453,721
Actual ratio | 0.1337 | 0.1288
Capital adequacy guidelines ratio | 0.0600 | 0.0600
Total risk-based capital ratio: |  |
Actual capital | $ 2,770,166 | $ 2,722,290
Actual ratio | 0.1480 | 0.1429
Capital adequacy guidelines ratio | 0.0800 | 0.0800
Tier 1 leverage ratio: |  |
Actual capital | $ 2,502,901 | $ 2,453,721
Actual ratio | 0.0959 | 0.0890
Capital adequacy guidelines ratio | 0.0400 | 0.0400
The Bank |  |
Common Equity Tier 1 risk-based capital ratio: |  |
Actual capital | $ 2,506,271 | $ 2,463,266
Actual ratio | 13.40% | 12.94%
Capital adequacy guidelines ratio | 4.50% | 4.50%
Categorized as well capitalized under prompt corrective action provisions ratio | 6.50% | 6.50%
Tier 1 risk-based capital ratio: |  |
Actual capital | $ 2,506,271 | $ 2,463,266
Actual ratio | 0.1340 | 0.1294
Capital adequacy guidelines ratio | 0.0600 | 0.0600
Categorized as well capitalized under prompt corrective action provisions ratio | 0.0800 | 0.0800
Total risk-based capital ratio: |  |
Actual capital | $ 2,721,890 | $ 2,681,116
Actual ratio | 0.1455 | 0.1408
Capital adequacy guidelines ratio | 0.0800 | 0.0800
Categorized as well capitalized under prompt corrective action provisions ratio | 0.1000 | 0.1000
Tier 1 leverage ratio: |  |
Actual capital | $ 2,506,271 | $ 2,463,266
Actual ratio | 0.0961 | 0.0894
Capital adequacy guidelines ratio | 0.0400 | 0.0400
Categorized as well capitalized under prompt corrective action provisions ratio | 0.0500 | 0.0500

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