GOODWILL AND INTANGIBLE ASSETS - Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	$ 1,012,620	$ 928,005
Additions related to acquisitions in current year	0	84,615
Fair value adjustments related to acquisitions in prior year	3,026	0
Carrying amount of goodwill at end of year	1,015,646	1,012,620
Banking Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	948,122	863,507
Additions related to acquisitions in current year	0	84,615
Fair value adjustments related to acquisitions in prior year	3,026	0
Carrying amount of goodwill at end of year	951,148	948,122
Premium Finance Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	64,498	64,498
Carrying amount of goodwill at end of year	$ 64,498	$ 64,498