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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Narrative (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) instrument	Dec. 31, 2021 USD ($)
Derivative [Line Items]
Derivative, notional amount	$ 4,524,514,000	$ 3,711,905,000
Amortized cost of securities pledged as collateral to derivative counterparties	12,000,000	34,800,000
Fair value of securities as pledged collateral to derivative counterparties	12,000,000	34,900,000
Cash pledged as collateral to derivative counterparties		43,700,000
Interest Rate Swap
Derivative [Line Items]
Cash pledged as collateral to derivative counterparties	0	43,694,000
Interest Rate Swap | Financial institutions counterparties
Derivative [Line Items]
Derivative asset, fair value, amount offset against collateral	51,200,000	2,200,000
Amount of collateral posted for the net liability positions	1,200,000	33,300,000
Interest Rate Swap | Commercial counterparties
Derivative [Line Items]
Cash pledged as collateral to derivative counterparties	0	0
Derivative asset, fair value, amount offset against collateral	1,000,000	76,800,000
Amount of collateral posted for the net liability positions	96,100,000	2,500,000
Non-hedging derivatives:
Derivative [Line Items]
Derivative, notional amount	$ 4,114,000	8,192,000
Economic Hedging | Tax advantaged economic development bonds
Derivative [Line Items]
Fixed rate of interest (percent)	5.09%
Maturity period (in years)	21 years
Economic Hedging | Interest Rate Swap | Tax advantaged economic development bonds
Derivative [Line Items]
Derivative, notional amount	$ 7,100,000
Economic Hedging | Hedging derivatives
Derivative [Line Items]
Derivative, notional amount	3,720,400,000	3,703,713,000
Economic Hedging | Hedging derivatives | Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	3,400,000,000
Economic Hedging | Hedging derivatives | Interest Rate Swap | Tax advantaged economic development bonds
Derivative [Line Items]
Derivative, notional amount	7,062,000	7,879,000
Economic Hedging | Hedging derivatives | Risk Participation Agreements
Derivative [Line Items]
Derivative, notional amount	341,885,000	320,981,000
Economic Hedging | Hedging derivatives | Forward Commitments
Derivative [Line Items]
Derivative, notional amount	927,000	$ 6,377,000
Cash Flow Hedging
Derivative [Line Items]
Derivative, notional amount	$ 800,000,000
Cash Flow Hedging | Interest Rate Swap
Derivative [Line Items]
Number of interest rate swap contracts (contract) | instrument	6
Cash Flow Hedging | Interest Rate Swap | Minimum
Derivative [Line Items]
Durations of derivative instruments	2 years
Cash Flow Hedging | Interest Rate Swap | Maximum
Derivative [Line Items]
Durations of derivative instruments	4 years
Cash Flow Hedging | Interest Rate Swap | Commercial Loan
Derivative [Line Items]
Derivative, notional amount	$ 400,000,000
Cash Flow Hedging | Interest Rate Collars
Derivative [Line Items]
Number of interest rate swap contracts (contract) | instrument	2
Cash Flow Hedging | Interest Rate Collars | Minimum
Derivative [Line Items]
Durations of derivative instruments	3 years
Cash Flow Hedging | Interest Rate Collars | Maximum
Derivative [Line Items]
Durations of derivative instruments	4 years
Cash Flow Hedging | Interest Rate Collars | Commercial Loan
Derivative [Line Items]
Derivative, notional amount	$ 200,000,000
Cash Flow Hedging | First Interest Rate Collars
Derivative [Line Items]
Derivative, notional amount	$ 100,000,000
Derivative, floor interest rate	3.00%
Derivative, cap interest rate	5.75%
Cash Flow Hedging | Second Interest Rate Collars
Derivative [Line Items]
Derivative, notional amount	$ 100,000,000
Derivative, floor interest rate	3.25%
Derivative, cap interest rate	5.75%
Cash Flow Hedging | Forward Starting Interest Rate Swaps
Derivative [Line Items]
Number of interest rate swap contracts (contract) | instrument	2
Cash Flow Hedging | Forward Starting Interest Rate Swaps | Commercial Loan
Derivative [Line Items]
Derivative, notional amount	$ 200,000,000
Cash Flow Hedging | Interest Rate Swap And Forward Starting INterest Rate Swap
Derivative [Line Items]
Derivative, notional amount	600,000,000
Cash Flow Hedging | Hedging derivatives | Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	600,000,000
Cash Flow Hedging | Hedging derivatives | Interest Rate Collars
Derivative [Line Items]
Derivative, notional amount	$ 200,000,000

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Fixed interest rate related to the interest rate derivative.

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