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v3.23.1

Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Fair Value of Derivatives (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) item | Dec. 31, 2022 USD ($) item
Two financial institutions |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Cash collateral pledged with financial institutions, dollars | $ 8,100,000 | $ 11,200,000
Number of correspondent financial institutions where investment securities are pledged | item |  | 2
Number of financial institutions in which cash collateral pledged | item |  | 2
Interest Rate Swap [Member] |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Cash collateral pledged with financial institutions, dollars | 2,800,000 | $ 5,300,000
Investment securities pledged with financial institutions, dollars | $ 0 | $ 0
Number of financial institutions in which cash collateral pledged | item | 1 | 1
Designated as Hedging Instrument |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative assets designated as hedging instruments, fair value | $ 1,824,000 | $ 2,737,000
Derivative liabilities designated as hedging instruments, fair value | 6,095,000 | 8,610,000
Designated as Hedging Instrument | Interest Rate Products | Cash flow hedges of certain variable rate commercial and commercial real estate loan pools |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Notional amount | 300,000,000.0 | 250,000,000.0
Designated as Hedging Instrument | Interest Rate Products | Cash flow hedge of junior subordinated debentures and was executed to pay fixed and receive variable rate cash flows |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Notional amount | $ 25,800,000 | $ 25,800,000
Designated as Hedging Instrument | Interest Rate Products | OSBC Affiliates |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative, number of transactions | item | 5 | 4
Notional amount | $ 325,774,000 | $ 275,774,000
Derivative assets designated as hedging instruments, fair value | 1,824,000 |
Derivative liabilities designated as hedging instruments, fair value | 6,095,000 | 8,610,000
Designated as Hedging Instrument | Interest Rate Swap [Member] | OSBC Affiliates |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative assets designated as hedging instruments, fair value |  | 2,737,000
Not Designated as Hedging Instrument |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative assets designated as hedging instruments, fair value | 4,089,000 |
Derivative liabilities designated as hedging instruments, fair value | 3,912,000 |
Not Designated as Hedging Instrument | Interest Rate Products |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Notional amount | $ 108,200,000 | $ 110,600,000
Not Designated as Hedging Instrument | Interest Rate Products | Commercial Loan Customers |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative, number of transactions | item | 19 | 21
Notional amount | $ 108,150,000 | $ 110,647,000
Derivative assets designated as hedging instruments, fair value | 3,911,000 | 3,654,000
Derivative liabilities designated as hedging instruments, fair value | 3,911,000 | 3,654,000
Not Designated as Hedging Instrument | Commitments. |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Notional amount | $ 10,900,000 | $ 5,300,000
Not Designated as Hedging Instrument | Interest Rate Lock Commitments and Forward Contracts. |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative, number of transactions | item | 41 | 4
Notional amount | $ 10,930,000 | $ 43,699,000
Derivative assets designated as hedging instruments, fair value | $ 28,000 | 125,000
Derivative liabilities designated as hedging instruments, fair value |  | $ 1,000
Not Designated as Hedging Instrument | Interest Rate Lock Commitments and Forward Contracts. | Commercial Loan Customers |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative, number of transactions | item |  | 28
Notional amount |  | $ 5,298,000
Derivative assets designated as hedging instruments, fair value |  | 76,000
Not Designated as Hedging Instrument | Other Contracts |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Derivative, number of transactions | item | 4 |
Notional amount | $ 44,097,000 |
Derivative assets designated as hedging instruments, fair value | 150,000 | 3,855,000
Derivative liabilities designated as hedging instruments, fair value | 1,000 | $ 3,655,000
Interest Income |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount to be reclassified as an decrease to interest expense during the next twelve months | 5,000,000.0 |
Interest Expense |  |
Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions |  |
Amount to be reclassified as an decrease to interest expense during the next twelve months | $ 511,000 |

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