GOODWILL AND INTANGIBLE ASSETS - Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	$ 931,637	$ 503,434
Additions related to acquisitions in current year	0	430,497
Fair value adjustments related to acquisitions in prior year	(3,632)	(2,294)
Carrying amount of goodwill at end of year	928,005	931,637
Banking Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	867,139	438,144
Additions related to acquisitions in current year	0	430,497
Fair value adjustments related to acquisitions in prior year	(3,632)	(1,502)
Carrying amount of goodwill at end of year	863,507	867,139
Premium Finance Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	64,498	65,290
Fair value adjustments related to acquisitions in prior year	0	(792)
Carrying amount of goodwill at end of year	$ 64,498	$ 64,498

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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