Securities - Schedule of Amortized Cost and Estimated Fair Value of Securities Available for Sale by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Available for sale, Within one year, Amortized Cost	$ 1,000
Available for sale, One to five years, Amortized Cost	938
Available for sale, Amortized Cost	101,968	$ 90,599
Available for sale, Within one year, Fair Value	1,001
Available for sale, One to five years, Fair Value	978
Available for sale, Fair Value	102,413	91,791
Mortgage-backed Securities, Residential
Schedule Of Available For Sale Securities [Line Items]
Available for sale, debt maturities Amortized Cost	24,258
Available for sale, Amortized Cost	25,196	19,281
Available for sale, debt maturities Fair Value	24,450
Available for sale, Fair Value	25,428	19,704
Collateralized Mortgage Obligations, Residential
Schedule Of Available For Sale Securities [Line Items]
Available for sale, Amortized Cost	75,772	70,318
Available for sale, Fair Value	$ 75,984	$ 71,082

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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