Fair Value Measurements - Summary of Assets and Liabilities at Carrying Value and Estimated Fair Value on a Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Assets:
Cash and due from banks	$ 9,324	$ 6,096	[1]
Federal funds sold	152	1,359	[1]
Certificates of deposit	1,266	2,754	[1]
Restricted securities	5,022	5,706	[1]
Loans receivable, net	1,041,711	916,628	[1]
Loans held for sale	2,687	1,231	[1]
Accrued interest receivable	4,664	3,035	[1]
Financial Liabilities:
Savings and interest-bearing demand deposits	424,001	382,607	[1]
Time deposits	412,837	389,900	[1]
Securities sold under repurchase agreements	1,117	6,525	[1]
FHLB advances	25,000	45,000	[1]
FRB advances	32,637
Subordinated notes, net	31,083	31,001	[1]
Fair Value, Inputs, Level 1
Financial Assets:
Cash and due from banks	9,324	6,096
Interest-earning deposits	50,069	34,358
Federal funds sold	152	1,359
Financial Liabilities:
Noninterest-bearing demand deposits	190,843	137,933
Savings and interest-bearing demand deposits	424,001	382,607
Securities sold under repurchase agreements	1,117	6,525
FRB advances	32,637
Fair Value, Inputs, Level 2
Financial Assets:
Certificates of deposit	1,266	2,754
Loans held for sale	2,687	1,231
Accrued interest receivable	4,664	3,035
Financial Liabilities:
FHLB advances	24,849	44,936
Fair Value, Inputs, Level 3
Financial Assets:
Restricted securities	5,022	5,706
Loans receivable, net	1,041,429	910,678
Financial Liabilities:
Time deposits	419,752	392,562
Subordinated notes, net	33,087	32,552
Carrying Value
Financial Assets:
Cash and due from banks	9,324	6,096
Interest-earning deposits	50,069	34,358
Federal funds sold	152	1,359
Certificates of deposit	1,266	2,754
Restricted securities	5,022	5,706
Loans receivable, net	1,041,711	916,628
Loans held for sale	2,687	1,231
Accrued interest receivable	4,664	3,035
Financial Liabilities:
Noninterest-bearing demand deposits	190,843	137,933
Savings and interest-bearing demand deposits	424,001	382,607
Time deposits	412,837	389,900
Securities sold under repurchase agreements	1,117	6,525
FHLB advances	25,000	45,000
FRB advances	32,637
Subordinated notes, net	31,083	31,001
Fair Value
Financial Assets:
Cash and due from banks	9,324	6,096
Interest-earning deposits	50,069	34,358
Federal funds sold	152	1,359
Certificates of deposit	1,266	2,754
Restricted securities	5,022	5,706
Loans receivable, net	1,041,429	910,678
Loans held for sale	2,687	1,231
Accrued interest receivable	4,664	3,035
Financial Liabilities:
Noninterest-bearing demand deposits	190,843	137,933
Savings and interest-bearing demand deposits	424,001	382,607
Time deposits	419,752	392,562
Securities sold under repurchase agreements	1,117	6,525
FHLB advances	24,849	44,936
FRB advances	32,637
Subordinated notes, net	$ 33,087	$ 32,552

[1] Derived from audited December 31, 2019 Consolidated Financial Statements.