PARENT COMPANY ONLY CONDENSED FINANCIAL INFORMATION, Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Interest expense	$ (72,286)	$ (22,692)	$ (13,272)
Other expense	(16,118)	(17,522)	(17,883)
Income before income taxes	79,417	73,151	73,121
Income tax benefit	16,672	14,911	14,507
Net income	62,745	58,240	58,614
South Plains Financial, Inc. [Member]
Income Statement [Abstract]
Dividends	35,000	40,375	48,250
Other income	100	52	26
Interest expense	(7,294)	(5,689)	(4,936)
Other expense	(1,897)	(1,768)	(1,466)
Income before income taxes	25,909	32,970	41,874
Income tax benefit	(1,904)	(1,555)	(1,339)
Equity in undistributed subsidiary income	34,932	23,715	15,401
Net income	$ 62,745	$ 58,240	$ 58,614