Investment Securities - Summary of Interest Income On Available-For-Sale Investment Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	$ 6,452	$ 5,214	$ 3,863
Total tax-exempt interest income	120	267	367
Total	6,572	5,481	4,230
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	4,170	3,682	2,983
Other
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	2,282	1,532	880
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Total tax-exempt interest income	$ 120	$ 267	$ 367

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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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.

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