Carrying amount as of the balance sheet date of loan pool hedge for securities.

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Represents the number of financial institutions where investment securities are pledged.

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No definition available.

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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

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Fair value of all liability derivatives designated as cash flow hedging instruments.

+ References

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Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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

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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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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.

+ References

No definition available.

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Nominal or face amount used to calculate payment on derivative.

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

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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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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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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

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Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for debt facilities other than FHLB loans, repurchase agreements and letter of credit arrangements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

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Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Fair Value of Derivatives (Details)	1 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2021 USD ($) item	Dec. 31, 2020 USD ($) item
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Loan pool hedge	$ 50,000,000.0
Term of interest rate risk cash flow hedge	5 years
Amount of ineffectiveness, included in net income		$ 0
Weighted average maturity			4 years 8 months 12 days
Interest Rate Products
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Notional Amount		25,800,000
Designated as Hedging Instrument [Member]
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative assets designated as hedging instruments, fair value		1,567,000
Derivative liabilities designated as hedging instruments, fair value		$ 4,042,000
Designated as Hedging Instrument [Member] \| Interest Rate Products
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative assets designated as hedging instruments, classified in other assets			$ 2,697,000
Derivative liabilities designated as hedging instruments, fair value			$ 6,380,000
Designated as Hedging Instrument [Member] \| Interest Rate Products \| OSBC Affiliates
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative, number of transactions \| item		2	2
Notional Amount		$ 75,774,000	$ 75,774,000
Derivative assets designated as hedging instruments, classified in other assets		1,567,000
Derivative liabilities designated as hedging instruments, classified in other liabilities		4,042,000	6,380,000
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| OSBC Affiliates
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative assets designated as hedging instruments, classified in other assets			$ 2,697,000
Not Designated as Hedging Instrument [Member]
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative assets not designated as hedging instruments, fair value		4,600,000
Total Derivative liabilities not designated as hedging instruments, fair value		$ 3,756,000
Not Designated as Hedging Instrument [Member] \| Interest Rate Products \| Commercial Loan Customers
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative, number of transactions \| item		26	28
Notional Amount		$ 167,218,000	$ 189,126,000
Interest rate derivatives, derivative assets not designated as hedging instruments, classified in other assets		3,725,000	6,691,000
Interest rate derivatives, derivative not designated as hedging instruments, classified in other liabilities		$ 3,725,000	6,691,000
Weighted average maturity		4 years 1 month 6 days
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Cash collateral pledged with financial institutions, dollars	$ 17,200,000	$ 740,000	1,400,000
Investment securities pledged with financial institutions, dollars		$ 0	$ 0
Number of correspondent financial institutions where investment securities are pledged \| item		1	1
Not Designated as Hedging Instrument [Member] \| Interest Rate Lock Commitments and Forward Contracts
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative, number of transactions \| item		132	4
Notional Amount		$ 46,753,000	$ 26,523,000
Interest rate derivatives, derivative assets not designated as hedging instruments, classified in other assets		$ 875,000
Interest rate derivatives, derivative not designated as hedging instruments, classified in other liabilities			$ 88,000
Not Designated as Hedging Instrument [Member] \| Interest Rate Lock Commitments and Forward Contracts \| Commercial Loan Customers
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative, number of transactions \| item			205
Notional Amount			$ 84,472,000
Interest rate derivatives, derivative assets not designated as hedging instruments, classified in other assets			840,000
Not Designated as Hedging Instrument [Member] \| Other Contracts
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Derivative, number of transactions \| item		3
Notional Amount		$ 17,297,000
Derivative assets designated as hedging instruments, classified in other assets			7,531,000
Derivative liabilities designated as hedging instruments, classified in other liabilities			$ 6,779,000
Interest rate derivatives, derivative not designated as hedging instruments, classified in other liabilities		31,000
Interest Income [Member]
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Amount to be reclassified as a reduction to interest expense during the next twelve months		189,000
Interest Expense [Member]
Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk
Amount to be reclassified as a reduction to interest expense during the next twelve months		$ 175,000