GOODWILL AND INTANGIBLE ASSETS - Carrying Value of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	$ 125,532	$ 125,532
Additions related to acquisitions in current year	377,902	0
Carrying amount of goodwill at end of year	503,434	125,532
Banking Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	125,532	125,532
Additions related to acquisitions in current year	312,612	0
Carrying amount of goodwill at end of year	438,144	125,532
Premium Finance Division
Goodwill [Roll Forward]
Carrying amount of goodwill at beginning of year	0	0
Additions related to acquisitions in current year	65,290	0
Carrying amount of goodwill at end of year	$ 65,290	$ 0

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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