Available for Sale Securities - Summary of Amortized Costs and Fair Values of Securities Available-for-sale, by Contractual Maturity (Detail) $ in Thousands	Sep. 30, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	$ 326
Due after one through 5 years	6,682
Due after 5 through 10 years	1,444
Due after 10 years	1,044
Fair Value	9,496
Total	58,428
Due in one year or less	326
Due after one through 5 years	6,462
Due after 5 through 10 years	1,329
Due after 10 years	1,000
Amortized Cost	9,117
Total	56,730
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	41,554
Amortized Cost	40,244
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	7,378
Amortized Cost	$ 7,369

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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