Investment Securities - Summary of Interest Income On Available-For-Sale Investment Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	$ 5,214	$ 3,863	$ 3,298
Total tax-exempt interest income	267	367	282
Total	5,481	4,230	3,580
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	3,682	2,983	2,661
U.S. Agency Mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	0	0	4
Other
Debt Securities, Available-for-sale [Line Items]
Total taxable interest income	1,532	880	633
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Total tax-exempt interest income	$ 267	$ 367	$ 282

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=114873765&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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+ References

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