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DEPOSITS - Narrative (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Deposit Liabilities Disclosures [Line Items] |  |  |
Interest expense on time deposits of $250,000 or more | $ 13,000,000 | $ 2,100,000 | $ 1,400,000
Maximum brokered certificates of deposit balance allowed per company policy | $ 1,200,000,000 |  |
Maximum brokered certificates of deposit balance allowed per company policy, percent | 20.00% |  |
Related party deposit liabilities | $ 9,800,000 | 11,000,000 |
Demand deposit overdrafts reclassified as loans | 1,300,000 | 1,200,000 |
Certificates of deposit - CDs |  |  |
Deposit Liabilities Disclosures [Line Items] |  |  |
Brokered deposits | 0 | 220,900,000 |
Brokered non-maturity deposits |  |  |
Deposit Liabilities Disclosures [Line Items] |  |  |
Brokered deposits | $ 828,000,000 | $ 438,400,000 |
Weighted average cost, domestic deposit, brokered | 3.23% |  |

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- Definition Interest-bearing Domestic Deposit, Brokered, Maximum Balance Allowed per Company Policy + References No definition available. + Details
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- Definition Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -SubTopic 405 -Topic 942 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481047/942-405-50-1 + Details
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- Definition Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.12) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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- Definition Amount of deposits held by the entity for a related party (entity, shareholder, employee). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 + Details
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