Condensed Financial Information (Parent Company Only) - Condensed Statements of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities
Net income (loss)	$ 62,621	$ 7,821	$ 57,688
Adjustments to reconcile net income to net cash from operating activities:
Stock based compensation	4,048	3,213	3,325
Net amortization of purchase valuation adjustments	(1,997)	(618)	(3,979)
Loss (gain) on sales and valuation adjustments on other real estate owned	(7,906)	218	80
Change in unrealized (gains) losses on equity securities	(487)	(104)	74
Change in fair value of derivatives recognized in earnings	(95)	522	(1,477)
Net change in:
Other assets	11,224	6,166	22,466
Interest payable and other liabilities	1,297	5,767	(17,575)
Net cash provided by operating activities	73,845	76,527	74,073
Cash flows (to) from investing activities
Proceeds from sales, calls, pay-downs and maturities of AFS securities	288,344	789,390	168,409
Net redemptions (purchases) of correspondent and miscellaneous other stock	(543)	(11,855)	(4,546)
Proceeds from sale of other real estate owned	9,397	1,874	9,323
Net cash (used in) provided by investing activities	123,729	232,170	(214,184)
Cash flows (to) from financing activities
Principal payments on bank stock loan	(691)
Proceeds from issuance of common stock, net	86,980
Proceeds from exercise of employee stock options	3,506	203	2,011
Proceeds from employee stock purchase plan	726	784	792
Dividends paid on common stock	(7,892)	(6,614)	(5,564)
Net cash provided by (used in) financing activities	(192,926)	(34,026)	(15,415)
Net change in cash and cash equivalents	4,648	274,671	(155,526)
Cash and cash equivalents, beginning of period	379,099	104,428	259,954
Ending cash and cash equivalents	383,747	379,099	104,428
Equity Bancshares, Inc. [Member]
Cash flows from operating activities
Net income (loss)	62,621	7,821	57,688
Adjustments to reconcile net income to net cash from operating activities:
Stock based compensation	4,048	3,213	3,325
Equity in undistributed (income) loss	(35,468)	17,844	(31,462)
Net amortization of purchase valuation adjustments	555	530	506
Loss (gain) on sales and valuation adjustments on other real estate owned	(8,500)
Change in unrealized (gains) losses on equity securities	(294)
Change in fair value of derivatives recognized in earnings	4
Net change in:
Other assets	(4,938)	(658)	1,464
Interest payable and other liabilities	(3,175)	(2,556)	(5,912)
Net cash provided by operating activities	13,760	24,949	26,017
Cash flows (to) from investing activities
Net redemptions (purchases) of correspondent and miscellaneous other stock	(493)	(751)	(2,425)
Proceeds from sale of other real estate owned	8,500
Net cash (paid) received from acquisition	(95)
Net cash (used in) provided by investing activities	7,812	(801)	(3,025)
Cash flows (to) from financing activities
Principal payments on bank stock loan	(691)
Proceeds from issuance of common stock, net	86,980
Proceeds from exercise of employee stock options	3,506	203	2,011
Proceeds from employee stock purchase plan	726	784	792
Purchase of treasury stock	(11,859)	(17,900)	(33,186)
Dividends paid on common stock	(7,892)	(6,614)	(5,564)
Net cash provided by (used in) financing activities	70,770	(23,527)	(35,947)
Net change in cash and cash equivalents	92,342	621	(12,955)
Cash and cash equivalents, beginning of period	12,729	12,108	25,063
Ending cash and cash equivalents	105,071	12,729	12,108
EBAC [Member] | Equity Bancshares, Inc. [Member]
Adjustments to reconcile net income to net cash from operating activities:
Equity in undistributed (income) loss	358	305	413
Cash flows (to) from investing activities
Additional investment	(100)	(50)	(200)
ERMI [Member] | Equity Bancshares, Inc. [Member]
Adjustments to reconcile net income to net cash from operating activities:
Equity in undistributed (income) loss	$ (1,451)	$ (1,550)	(5)
Cash flows (to) from investing activities
Additional investment			$ (400)