GOODWILL AND INTANGIBLE ASSETS - Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	$ 503,434	$ 125,532
Additions related to acquisitions in current year	430,497	377,902
Fair value adjustments related to acquisitions in prior year	(2,294)	0
Carrying amount of goodwill at end of year	931,637	503,434
Banking Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	438,144	125,532
Additions related to acquisitions in current year	430,497	312,612
Fair value adjustments related to acquisitions in prior year	(1,502)	0
Carrying amount of goodwill at end of year	867,139	438,144
Premium Finance Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	65,290	0
Additions related to acquisitions in current year	0	65,290
Fair value adjustments related to acquisitions in prior year	(792)	0
Carrying amount of goodwill at end of year	$ 64,498	$ 65,290

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.

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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

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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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