Investment Securities - Summary of Interest Income on Available-for-Sale Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	$ 824	$ 917	$ 2,408	$ 3,879
Total tax-exempt interest income	4	23	13	72
Total interest income	828	940	2,421	3,951
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	552	680	1,568	2,839
Other
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	272	237	840	1,040
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Total tax-exempt interest income	$ 4	$ 23	$ 13	$ 72

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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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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