Borrowings - Schedule of Future Principal Repayments (Detail) $ in Thousands	Mar. 31, 2021 USD ($)
Debt Instrument Redemption [Line Items]
Due in one year or less	$ 42,696
Due after one year through two years	2,357
Due after two years through three years	2,357
Due after three years through four years	1,857
Due after four years through five years	965
Thereafter	95,620
Total	145,852
Retail Repurchase Agreements [Member]
Debt Instrument Redemption [Line Items]
Due in one year or less	40,339
Total	40,339
Federal Home Loan Bank Advances [Member]
Debt Instrument Redemption [Line Items]
Due in one year or less	2,357
Due after one year through two years	2,357
Due after two years through three years	2,357
Due after three years through four years	1,857
Due after four years through five years	965
Total	9,893
Subordinated Debentures [Member]
Debt Instrument Redemption [Line Items]
Thereafter	20,620
Total	20,620
Subordinated Notes [Member]
Debt Instrument Redemption [Line Items]
Thereafter	75,000
Total	$ 75,000