Investment Securities - Summary of Interest Income on Available-For-Sale Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	$ 1,516	$ 1,250	$ 4,756	$ 3,656
Total tax-exempt interest income	12	64	94	214
Total interest income	1,528	1,314	4,850	3,870
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	943	867	3,085	2,652
Other
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	573	383	1,671	1,004
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Total tax-exempt interest income	$ 12	$ 64	$ 94	$ 214

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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