LOANS - Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Allowance for loan losses
Total	$ 2,577,306	$ 2,490,227
Commercial real estate
Allowance for loan losses
Total	923,773	826,699
Commercial and industrial
Allowance for loan losses
Total	402,706	404,870
Residential real estate
Allowance for loan losses
Total	1,143,452	1,144,698
Consumer
Allowance for loan losses
Total	107,375	113,960
Business Activities Loans
Allowance for loan losses
Individually evaluated for impairment	12,738	13,855
Collectively evaluated	1,815,398	1,617,042
Total	1,828,136	1,630,897
Business Activities Loans \| Commercial real estate
Allowance for loan losses
Individually evaluated for impairment	8,759	9,835
Collectively evaluated	692,928	569,899
Total	701,687	579,734
Business Activities Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	1,323	1,445
Collectively evaluated	325,820	312,217
Total	327,143	313,662
Business Activities Loans \| Residential real estate
Allowance for loan losses
Individually evaluated for impairment	2,643	2,562
Collectively evaluated	727,873	667,627
Total	730,516	670,189
Business Activities Loans \| Consumer
Allowance for loan losses
Individually evaluated for impairment	13	13
Collectively evaluated	68,777	67,299
Total	68,790	67,312
Acquired Loans
Allowance for loan losses
Individually evaluated for impairment	1,644	1,358
Purchased credit impaired	8,410	10,106
Collectively evaluated	739,116	847,866
Total	749,170	859,330
Acquired Loans \| Commercial real estate
Allowance for loan losses
Individually evaluated for impairment	257	188
Purchased credit impaired	5,049	6,307
Collectively evaluated	216,780	240,470
Total	222,086	246,965
Acquired Loans \| Commercial and industrial
Allowance for loan losses
Individually evaluated for impairment	414	426
Purchased credit impaired	249	679
Collectively evaluated	74,900	90,103
Total	75,563	91,208
Acquired Loans \| Residential real estate
Allowance for loan losses
Individually evaluated for impairment	973	744
Purchased credit impaired	3,093	3,095
Collectively evaluated	408,870	470,670
Total	412,936	474,509
Acquired Loans \| Consumer
Allowance for loan losses
Individually evaluated for impairment	0	0
Purchased credit impaired	19	25
Collectively evaluated	38,566	46,623
Total	$ 38,585	$ 46,648

Financing Receivable, Purchased Credit-Impaired Loans

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No definition available.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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