Loans - Summary of balance in allowance for loan losses and recorded investment in loans by class and based on impairment method (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 0	$ 0
Collectively evaluated for impairment	8,878	6,989
Total ending allowance balance	8,878	6,989	$ 6,049	$ 5,629
Loans:
Loans individually evaluated for impairment	750	1,476
Loans collectively evaluated for impairment	589,269	563,503
Total ending loans balance	590,019	564,979
Real Estate \| 1 - 4 Family Residential
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	497	344
Total ending allowance balance	497	344	380	407
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	51,738	48,140
Total ending loans balance	51,738	48,140
Real Estate \| Multifamily
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,441	1,048
Total ending allowance balance	1,441	1,048	949	952
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	147,333	152,633
Total ending loans balance	147,333	152,633
Real Estate \| Commercial Real Estate
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	817	560
Total ending allowance balance	817	560	408	357
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	51,126	52,477
Total ending loans balance	51,126	52,477
Real Estate \| Construction
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment		161
Total ending allowance balance		161	159	149
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment		6,450
Total ending loans balance		6,450
Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	5,086	4,048
Total ending allowance balance	5,086	4,048	3,486	3,110
Loans:
Loans individually evaluated for impairment	0	0
Loans collectively evaluated for impairment	292,343	257,957
Total ending loans balance	292,343	257,957
Consumer
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,037	828
Total ending allowance balance	1,037	828	$ 667	$ 654
Loans:
Loans individually evaluated for impairment	750	1,476
Loans collectively evaluated for impairment	46,729	45,846
Total ending loans balance	$ 47,479	$ 47,322

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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