Fair value of securities received as collateral against derivative assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal or face amount used to calculate payment on derivative.

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-Publisher FASB
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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Derivative , Number Of Instruments Terminated

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Number Of Financial Institutions

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DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) institution instrument	Dec. 31, 2021 USD ($) instrument	Dec. 31, 2020 USD ($) instrument
Derivative [Line Items]
Number of instruments terminated \| instrument			3
Interest rate cash flow hedge gain reclassified to interest income	$ 0.1
Interest rate cash flow hedge increase interest income to be reclassified during next 12 months net	$ 0.2
Number of variable-rate to fixed-rate swap transactions \| instrument	259	261
Minimum
Derivative [Line Items]
Remaining maturity period	1 year
Maximum
Derivative [Line Items]
Remaining maturity period	14 years
Interest rate swap
Derivative [Line Items]
Number of variable-rate to fixed-rate swap transactions \| instrument	82	193
Notional amount	$ 1,100.0	$ 1,100.0
Derivative liability	$ 6.6	35.8
Swap Guarantee
Derivative [Line Items]
Number of financial institutions \| institution	5
Derivative liability	$ 12.5	$ 13.1
Securities
Derivative [Line Items]
Collateral value against obligations	6.0
Cash
Derivative [Line Items]
Collateral value against obligations	$ 7.2
Designated as Hedging Instrument
Derivative [Line Items]
Termination value of derivatives			$ 1.3