Fair Value - Fair Value of Assets Measured on Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financial Assets
Available-for-sale debt securities	$ 1,546,155	$ 1,398,157
Loans held for sale	49,597	68,890
Other real estate owned	13,628	12,750
Fair Value, Measurements, Recurring
Financial Assets
Available-for-sale debt securities	1,546,155	1,398,157
Derivative financial instruments	9,624	14,343
Loans held for sale	49,597	68,890
Equity securities	9,404	6,530
Financial Liabilities
Derivative financial instruments	9,110	13,339
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets
Available-for-sale debt securities	199	101
Derivative financial instruments	0	0
Loans held for sale	0	0
Equity securities	9,404	6,530
Financial Liabilities
Derivative financial instruments	0	0
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Financial Assets
Available-for-sale debt securities	1,545,956	1,398,056
Derivative financial instruments	9,624	14,343
Loans held for sale	49,597	68,890
Equity securities	0	0
Financial Liabilities
Derivative financial instruments	9,110	13,339
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Financial Assets
Available-for-sale debt securities	0	0
Derivative financial instruments	0	0
Loans held for sale	0	0
Equity securities	0	0
Financial Liabilities
Derivative financial instruments	0	0
Fair Value, Measurements, Nonrecurring
Financial Assets
Loans	9,945	8,806
Other real estate owned	13,628	12,750
Fair Value, Measurements, Nonrecurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets
Loans	0	0
Other real estate owned	0	0
Fair Value, Measurements, Nonrecurring \| Significant Other Observable Inputs (Level 2)
Financial Assets
Loans	942	1,900
Other real estate owned	390	72
Fair Value, Measurements, Nonrecurring \| Significant Unobservable Inputs (Level 3)
Financial Assets
Loans	9,003	6,906
Other real estate owned	$ 13,238	$ 12,678

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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