GOODWILL, OTHER INTANGIBLE ASSETS AND MORTGAGE SERVICING RIGHTS (Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 339,154	$ 242,659
Goodwill, Acquired During Period		96,495
Goodwill, end of period	339,154	339,154
Finite-lived Intangible Assets [Roll Forward]
Goodwill and other intangibles, net, beginning of period	372,078	265,314
Additions through acquisitions		112,863
Amortization	(6,097)	(6,099)
Goodwill adjustments	(217)
Goodwill and other intangibles, net, end of period	365,764	372,078
Core Deposit Intangibles [Member]
Finite-lived Intangible Assets [Roll Forward]
Finite lived assets Balance, beginning of period	32,699	22,378
Intangible assets, additions through acquisitions		16,368
Amortization	(6,089)	(6,047)
Finite lived assets Balance, end of period	26,610	32,699
Leasehold Improvements [Member]
Finite-lived Intangible Assets [Roll Forward]
Finite lived assets Balance, beginning of period	225	277
Intangible assets, additions through acquisitions		0
Amortization	(8)	(52)
Goodwill adjustments	(217)
Finite lived assets Balance, end of period	$ 0	$ 225

Acquired Intangible Assets (Including Goodwill)

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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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No definition available.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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.

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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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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

+ References

No definition available.

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