Debt Securities - Additional Information (Details) $ in Thousands	Mar. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Schedule of Available-for-sale Securities
Pledged securities	$ 516,100	$ 434,700
Securities in continuous unrealized loss position \| security	203	57
Accumulated unrealized losses	$ 17,826	$ 1,314
Interest receivable	$ 19,749	$ 21,706
State and political subdivisions
Schedule of Available-for-sale Securities
Securities in continuous unrealized loss position \| security	145	27
Accumulated unrealized losses	$ 7,707	$ 483
Mortgage-backed securities
Schedule of Available-for-sale Securities
Securities in continuous unrealized loss position \| security	8	7
Accumulated unrealized losses	$ 744	$ 1
Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Securities in continuous unrealized loss position \| security	22	8
Accumulated unrealized losses	$ 5,677	$ 214
Mortgage backed securities and collateralized mortgage obligations
Schedule of Available-for-sale Securities
Accumulated unrealized losses	$ 6,400
Corporate debt securities
Schedule of Available-for-sale Securities
Securities in continuous unrealized loss position \| security	28	15
Accumulated unrealized losses	$ 3,698	$ 616
Debt securities
Schedule of Available-for-sale Securities
Interest receivable	$ 7,800	$ 7,300

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
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