Annual gross revenue benchmark to qualify as emerging growth company.

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Period for company qualifies as emerging growth company from completion of stock offering.

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Reorganization cost and issuing of common stock deferred.

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Face amount or stated value per share of common stock.

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The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 08, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of shares sold	4,876,677,000		2,145,738,000
Per share of common stock	$ 0.01		$ 10.00
Number of shares contributed			2,682,172,000
Reorganization Cost And Issuing Of Common Stock Deferred	$ 1,816,000
Foreclosed assets	0	$ 0
Other comprehensive income (loss) tax	0	18,000
Residential Real Estate [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans in process of foreclosure	240,000	$ 161,000
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Annual gross revenue benchmark to qualify as emerging growth company	$ 1,000,000,000
Period for company qualifies as emerging growth company from completion of stock offering	5 years
Common Stock [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Bank's employee stock issued			175,528,000
Charitable Foundation [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of shares contributed			48,767,000