Commitments and Contingencies - Summary of Distribution of Undisbursed Loan Commitments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Undisbursed loan commitments	$ 76,929	$ 74,641
Commitments to Extend Credit
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Undisbursed loan commitments	68,917	66,153
Standby Letter of Credit
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Undisbursed loan commitments	7,327	7,377
Commercial Letter of Credit
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Undisbursed loan commitments	$ 685	$ 1,111