GOODWILL AND OTHER INTANGIBLE ASSETS - Net Carrying Amount of Goodwill By Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Beginning balance	$ 363,436	$ 370,223
No Activity	0
Ending balance	363,436	363,436
Disposal of subsidiary's assets		(6,787)
Community Banking
Goodwill [Roll Forward]
Beginning balance	331,689	331,689
No Activity	0
Ending balance	331,689	331,689
Disposal of subsidiary's assets		0
Insurance
Goodwill [Roll Forward]
Beginning balance	0	6,787
No Activity	0
Ending balance	0	0
Disposal of subsidiary's assets		(6,787)
Investment Management
Goodwill [Roll Forward]
Beginning balance	31,747	31,747
No Activity	0
Ending balance	$ 31,747	31,747
Disposal of subsidiary's assets		$ 0