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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Derivative [Line Items] |  |
Derivative asset, statement of financial position [extensible enumeration] | Other assets | Other assets
Derivative liability, statement of financial position [extensible enumeration] | Other liabilities | Other liabilities
Notional amount | $ 15,349,000,000 | $ 15,924,000,000
Additional amount in excess of posted collateral required in case of breached agreements | $ 100,000 | 200,000
Interest rate contracts |  |
Derivative [Line Items] |  |
Maximum length of time hedged in interest rate cash flow hedge | 4 years |
Period to reclassification of cash flow hedge gain loss | 12 months |
Derivative gain to be reclassified within twelve months | $ 5,600,000 |
Derivative gain to be reclassified within twelve months, net of tax | 4,400,000 |
Derivative gain or losses excluded from assessment of hedge effectiveness | 0 |
Amount of gain (loss) reclassified from AOCI into net income | $ 0 | 0
Interest rate lock commitments | Minimum |  |
Derivative [Line Items] |  |
Lock in period for interest rates | 30 days |
Interest rate lock commitments | Maximum |  |
Derivative [Line Items] |  |
Lock in period for interest rates | 360 days |
Credit risk contracts |  |
Derivative [Line Items] |  |
Notional amount | $ 604,000,000 |
Maximum exposure under credit risk agreement assuming customer default | 0 | 0
Credit risk derivatives, purchased at fair value | 100,000 | 100,000
Credit risk derivatives, sold at fair value | $ 100,000 | $ 0
Credit risk contracts | Minimum |  |
Derivative [Line Items] |  |
Risk participation agreements, term | 3 months |
Credit risk contracts | Maximum |  |
Derivative [Line Items] |  |
Risk participation agreements, term | 15 years |

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- Definition The estimated gross amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References No definition available. + Details
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- Definition The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 185 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-185 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4H -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H + Details
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- Definition The net gain (loss) relating to components of the gain (loss) on the cash flow hedging instrument excluded from the assessment of cash flow hedge effectiveness. Recognized in earnings. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 182 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-182 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4C -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 21 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-21 + Details
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