Regulatory Matters - Schedule of Regulatory Capital Requirements (Detail) $ in Thousands	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jan. 01, 2019
Actual, Total Capital (to risk- weighted assets)	$ 50,295	$ 49,259
Actual, Tier I Capital (to risk- weighted assets)	47,100	46,321
Actual, Tier I Capital (to average assets)	47,100	46,321
Actual, Common Equity Tier 1 (to risk-weighted assets)	$ 47,100	$ 46,321
Actual Ratio, Total Capital (to risk- weighted assets)	17.26	18.52
Actual Ratio, Tier I Capital (to risk- weighted assets)	16.16	17.41
Actual Ratio, Tier I Capital (to average assets)	10.62	11.41
Actual Ratio, Common Equity Tier 1 (to risk-weighted assets)	16.16	17.41
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 23,313	$ 21,278
Minimum Capital Requirement, Tier I Capital (to risk-weighted assets)	17,485	15,961
Minimum Capital Requirement, Tier I Capital (to average assets)	17,742	16,236
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 13,114	$ 11,971
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	8.00	8.00	8.0
Minimum Capital Requirement Ratio, Tier I Capital (to risk-weighted assets)	6.00	6.00	6.0
Minimum Capital Requirement Ratio, Tier I Capital (to average assets)	4.00	4.00	4.0
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	4.50%	4.50%	4.50%
Minimum To Be Well Capitalized Under Prompt Corrective, Total Capital (to risk-weighted assets)		$ 27,928
Minimum To Be Well Capitalized Under Prompt Corrective, Tier I Capital (to risk-weighted assets)		22,611
Minimum To Be Well Capitalized Under Prompt Corrective, Tier I Capital (to average assets)		16,236
Minimum To Be Well Capitalized Under Prompt Corrective, Common Equity Tier 1 (to risk-weighted assets)		$ 18,621
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Total Capital (to risk-weighted assets)		10.50
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Tier I Capital (to risk-weighted assets)		8.50
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Tier I Capital (to average assets)		4.00
Minimum To Be Well Capitalized Under Prompt Corrective Ratio, Common Equity Tier 1 (to risk-weighted assets)		7.00%
Fully Phased-In
Minimum Capital Requirement, Total Capital (to risk-weighted assets)	$ 30,599
Minimum Capital Requirement, Tier I Capital (to risk-weighted assets)	24,770
Minimum Capital Requirement, Tier I Capital (to average assets)	17,742
Minimum Capital Requirement, Common Equity Tier 1 (to risk-weighted assets)	$ 20,399
Minimum Capital Requirement Ratio, Total Capital (to risk-weighted assets)	10.50	10.5	10.5
Minimum Capital Requirement Ratio, Tier I Capital (to risk-weighted assets)	8.50	8.5	8.5
Minimum Capital Requirement Ratio, Tier I Capital (to average assets)	4.00	4.0
Minimum Capital Requirement Ratio, Common Equity Tier 1 (to risk-weighted assets)	7.00%	7.00%	7.00%

Common Equity Tier One Capital Required For Adequacy To Risk based Assets.

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