Federal Funds Purchased and Securities Sold Under Agreements to Repurchase - Schedule of Remaining Contractual Maturity in Repurchase Agreements (Detail) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Assets Sold under Agreements to Repurchase [Line Items]
Federal funds purchased	$ 39,055,000	$ 0
Repurchase agreements, Remaining contractual maturity of the agreements	32,900,000	29,300,000
Total	71,944,000	29,268,000
Overnight & Continuous [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Federal funds purchased	39,055,000
Total	40,504,000	1,062,000
30-90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Total	5,880,000	3,900,000
Greater Than 90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Total	25,560,000	24,306,000
US Treasury & Agency Securities [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements, Remaining contractual maturity of the agreements	32,889,000	29,268,000
US Treasury & Agency Securities [Member] | Overnight & Continuous [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements, Remaining contractual maturity of the agreements	1,449,000	1,062,000
US Treasury & Agency Securities [Member] | 30-90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements, Remaining contractual maturity of the agreements	5,880,000	3,900,000
US Treasury & Agency Securities [Member] | Greater Than 90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements, Remaining contractual maturity of the agreements	$ 25,560,000	$ 24,306,000