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Loans - Analysis of Allowance for Credit Losses (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | $ 21,575 | $ 17,283 | $ 17,283
Charge Offs | (122) | (94) | (827)
Recoveries | 62 | 43 | 298
Provision for credit losses-loans | 817 | 580 | 4,600
Provision for credit losses-off balance sheet credit exposures | 62 |  |
Other Non-interest expense related to unfunded |  | 35 | 221
Balance at ending of year |  | 17,847 | 21,575
Ending balance: individually evaluated for impairment |  | 1,535 | 1,996
Ending balance: collectively evaluated for impairment |  | 16,312 | 19,579
Ending balance: loans acquired with deteriorated credit quality |  |  | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | $ 2,446,652 | 1,962,220 | 2,356,387
Ending balance: individually evaluated for impairment |  | 12,624 | 8,857
Ending balance: collectively evaluated for impairment |  | 1,948,149 | 2,346,871
Ending balance: loans acquired with deteriorated credit quality |  | 1,447 | 659
Cumulative Effect, Period of Adoption, Adjustment [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Accounting Standards Update [Extensible Enumeration] | Accounting Standards Update 2016-13 [Member] |  |
Consumer Real Estate [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | $ 998 | 857 | 857
Recoveries | 7 | 5 | 20
Provision for credit losses-loans | (256) | 30 | 121
Balance at ending of year |  | 892 | 998
Ending balance: individually evaluated for impairment |  |  | 6
Ending balance: collectively evaluated for impairment |  | 892 | 992
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 502,968 | 410,064 | 494,423
Ending balance: individually evaluated for impairment |  | 692 | 569
Ending balance: collectively evaluated for impairment |  | 408,694 | 493,449
Ending balance: loans acquired with deteriorated credit quality |  | 678 | 405
Agricultural Real Estate [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 349 | 1,040 | 1,040
Provision for credit losses-loans | 26 | (434) | (691)
Balance at ending of year |  | 606 | 349
Ending balance: individually evaluated for impairment |  | 273 | 0
Ending balance: collectively evaluated for impairment |  | 333 | 349
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 227,599 | 195,901 | 220,514
Ending balance: individually evaluated for impairment |  | 6,670 | 2,280
Ending balance: collectively evaluated for impairment |  | 189,033 | 218,039
Ending balance: loans acquired with deteriorated credit quality |  | 198 | 195
Agricultural [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 751 | 709 | 709
Recoveries |  |  | 7
Provision for credit losses-loans | (35) | 135 | 35
Balance at ending of year |  | 844 | 751
Ending balance: individually evaluated for impairment |  |  | 0
Ending balance: collectively evaluated for impairment |  | 844 | 751
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 131,677 | 140,847 | 128,926
Ending balance: individually evaluated for impairment |  | 20 | 152
Ending balance: collectively evaluated for impairment |  | 140,827 | 128,774
Commercial Real Estate [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 11,924 | 9,130 | 9,130
Recoveries | 2 | 2 | 9
Provision for credit losses-loans | 661 | 441 | 2,785
Balance at ending of year |  | 9,573 | 11,924
Ending balance: individually evaluated for impairment |  | 632 | 438
Ending balance: collectively evaluated for impairment |  | 8,941 | 11,486
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 1,223,163 | 909,408 | 1,150,511
Ending balance: individually evaluated for impairment |  | 4,097 | 4,108
Ending balance: collectively evaluated for impairment |  | 905,076 | 1,146,389
Ending balance: loans acquired with deteriorated credit quality |  | 235 | 14
Commercial and Industrial [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 5,382 | 3,847 | 3,847
Charge Offs |  | (6) | (418)
Recoveries | 6 | 9 | 93
Provision for credit losses-loans | 191 | 216 | 1,860
Balance at ending of year |  | 4,066 | 5,382
Ending balance: individually evaluated for impairment |  | 630 | 1,551
Ending balance: collectively evaluated for impairment |  | 3,436 | 3,831
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 270,857 | 248,362 | 272,119
Ending balance: individually evaluated for impairment |  | 1,122 | 1,581
Ending balance: collectively evaluated for impairment |  | 246,904 | 270,493
Ending balance: loans acquired with deteriorated credit quality |  | 336 | 45
Consumer [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 891 | 625 | 625
Charge Offs | (122) | (88) | (409)
Recoveries | 47 | 27 | 169
Provision for credit losses-loans | 230 | 59 | 506
Balance at ending of year |  | 623 | 891
Ending balance: individually evaluated for impairment |  |  | 1
Ending balance: collectively evaluated for impairment |  | 623 | 890
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
FINANCING RECEIVABLES: |  |  |
Ending balance | 90,388 | 57,638 | 89,894
Ending balance: individually evaluated for impairment |  | 23 | 167
Ending balance: collectively evaluated for impairment |  | 57,615 | 89,727
Unallocated [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 18 | 34 | 34
Provision for credit losses-loans |  | 133 | (16)
Balance at ending of year |  | 167 | 18
Ending balance: collectively evaluated for impairment |  | 167 | 18
Ending balance: loans acquired with deteriorated credit quality |  | 0 | 0
Unfunded Loan Commitment & Letters of Credit [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | 1,262 | 1,041 | 1,041
Provision for credit losses-off balance sheet credit exposures | 62 |  |
Other Non-interest expense related to unfunded |  | 35 | 221
Balance at ending of year | 2,228 | 1,076 | 1,262
Ending balance: collectively evaluated for impairment |  | 1,076 | 1,262
Ending balance: loans acquired with deteriorated credit quality |  | $ 0 | 0
Unfunded Loan Commitment & Letters of Credit [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] |  |  |
ALLOWANCE FOR CREDIT LOSSES: |  |  |
Balance at beginning of year | $ 904 |  |
Balance at ending of year |  |  | $ 904

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