Securities Held-to-Maturity - Schedule of Securities Held-to-Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Debt instruments: Pass-through GSEs (amortized cost)	$ 411	$ 451
Federal Agency [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt instruments: Pass-through GSEs (amortized cost)	$ 411	$ 451

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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