Investment Securities - Summary of Interest Income on Available-For-Sale Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	$ 1,595	$ 1,580
Total tax-exempt interest income	27	52
Total interest income	1,622	1,632
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	1,161	1,071
Other
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	434	509
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Total tax-exempt interest income	$ 27	$ 52

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=116637391&loc=SL114874048-224260

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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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