PARENT COMPANY ONLY CONDENSED FINANCIAL INFORMATION, Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	7 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities [Abstract]
Net income		$ 29,220	$ 29,290
Adjustments [Abstract]
Stock based compensation		853	0
Net cash from operating activities		30,484	26,920
Cash flows from investing activities [Abstract]
Return of capital from subsidiary	$ 25,000
Net cash from investing activities		(213,493)	(184,092)
Cash flows from financing activities [Abstract]
Issuance of common stock		51,392	0
Payments to tax authorities for stock-based compensation		(351)	0
Cash dividends on common stock		(1,079)	(30,045)
Net cash from financing activities		95,119	108,598
Net change in cash and cash equivalents		(87,890)	(48,574)
Beginning cash and cash equivalents		245,989	294,563
Ending cash and cash equivalents	245,989	158,099	245,989
South Plains Financial, Inc. [Member]
Cash flows from operating activities [Abstract]
Net income		29,220	29,290
Adjustments [Abstract]
Equity in undistributed subsidiary income		(25,241)	(16,801)
Stock based compensation		853	0
Change in other assets		(1,601)	(456)
Change in other liabilities		541	468
Release of unearned ESOP shares		0	0
Net cash from operating activities		3,772	12,501
Cash flows from investing activities [Abstract]
Return of capital from subsidiary		0	2,500
Cash paid in WTSB business combination		(76,100)	0
Net cash from investing activities		(76,100)	2,500
Cash flows from financing activities [Abstract]
Proceeds from long-term borrowings		0	13,115
Repayments of long-term borrowings		(7,530)	0
Issuance of common stock		51,392	0
Payments to tax authorities for stock-based compensation		(351)	0
Share based liability conversion		11,450	0
Cash dividends on common stock		(1,079)	(30,045)
Net cash from financing activities		53,882	(16,930)
Net change in cash and cash equivalents		(18,446)	(1,929)
Beginning cash and cash equivalents		22,627	24,556
Ending cash and cash equivalents	$ 22,627	$ 4,181	$ 22,627

The cash inflow from share based liability conversion.

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