Business Combination and Asset Purchase - Summary of Carrying Amount of Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Oct. 01, 2021	Apr. 30, 2021
Perpetual Federal Savings Bank [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment	$ 303	$ 510	$ 728
Perpetual Federal Savings Bank [Member] | Consumer Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment	336	581	608
Perpetual Federal Savings Bank [Member] | Agricultural Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment	108	114	118
Perpetual Federal Savings Bank [Member] | Commercial Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment		5	234
Perpetual Federal Savings Bank [Member] | Commercial and Industrial [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment			$ 5
Ossian Financial Services, Inc. [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment	10	208		$ 1,309
Ossian Financial Services, Inc. [Member] | Consumer Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment	$ 20	22		24
Ossian Financial Services, Inc. [Member] | Agricultural Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment				981
Ossian Financial Services, Inc. [Member] | Commercial Real Estate [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment		222		315
Ossian Financial Services, Inc. [Member] | Commercial and Industrial [Member]
Business Acquisition [Line Items]
Carrying amount, net of fair value adjustment		$ 285		$ 314