Condensed Financial Information (Parent Company Only) - Condensed Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Cash and due from banks	$ 259,131	$ 280,150
Other	99,509	32,108
Total assets	5,137,631	4,013,356
LIABILITIES AND STOCKHOLDERS’ EQUITY
Bank stock loan	0
Subordinated debt	95,885	87,684
Interest payable and other liabilities	47,413	19,071
Total liabilities	4,637,000	3,605,707
Stockholders' equity	500,631	407,649	$ 478,060	$ 455,941
Total liabilities and stockholders’ equity	5,137,631	4,013,356
Equity Bancshares, Inc. [Member]
ASSETS
Cash and due from banks	25,063	31,970
Investment	572,414	452,304
Other	342	7,657
Total assets	601,357	495,846
LIABILITIES AND STOCKHOLDERS’ EQUITY
Subordinated debt	95,885	87,684
Interest payable and other liabilities	4,841	513
Total liabilities	100,726	88,197
Stockholders' equity	500,631	407,649
Total liabilities and stockholders’ equity	601,357	495,846
Equity Bancshares, Inc. [Member] | EBAC [Member]
ASSETS
Investment	$ 3,538	$ 3,915