SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022 USD ($) Segment	Dec. 31, 2021 USD ($)
Loans [Abstract]
Number of days principal or interest payments are past due for loans to be placed on nonaccrual status	90 days
Goodwill and Other Intangible Assets [Abstract]
Goodwill impairment loss	$ 0	$ 0
Leases [Abstract]
Right-of-use asset	8,284
Lease liability	9,234
Cumulative effect adjustment debit to retained earnings	$ 281,679	242,750
Segment Information [Abstract]
Number of reportable segments | Segment	2
Minimum [Member]
Allowance for Loan Losses [Abstract]
Threshold balance of loan to be specifically reviewed for impairment	$ 250
ASU 2016-02 [Member]
Leases [Abstract]
Right-of-use asset		9,400
Lease liability		10,300
City Bank [Member] | Bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	City Bank
Windmark Insurance Agency, Inc. ("Windmark") [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	Windmark Insurance Agency, Inc. (“Windmark”)
Ruidoso Retail, Inc. [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	Ruidoso Retail, Inc.
CB Provence, LLC [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	CB Provence, LLC
CBT Brushy Creek, LLC [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	CBT Brushy Creek, LLC
CBT Properties, LLC [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Consolidated Subsidiaries	CBT Properties, LLC
South Plains Financial Capital Trusts (SPFCT) III-V [Member] | Non-bank Subsidiary [Member]
Subsidiaries Information [Abstract]
Wholly-Owned, Equity Method Subsidiaries	South Plains Financial Capital Trusts (SPFCT) III-V
Substandard or Worse [Member] | Minimum [Member]
Allowance for Loan Losses [Abstract]
Threshold balance of loan to be specifically reviewed for impairment	$ 250
Customer Relationships [Member]
Goodwill and Other Intangible Assets [Abstract]
Estimated useful lives	5 years
Employment Agreements [Member]
Goodwill and Other Intangible Assets [Abstract]
Estimated useful lives	5 years
Core Deposit Intangible [Member] | Maximum [Member]
Goodwill and Other Intangible Assets [Abstract]
Estimated useful lives	10 years
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-02 [Member]
Leases [Abstract]
Cumulative effect adjustment debit to retained earnings		$ (717)