ACQUISITION OF FIRSTMERIT CORPORATION (Tables)	12 Months Ended
Dec. 31, 2017
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition
Business Acquisition, Pro Forma Information

Tabular disclosure of a material business combination completed during the period, including background, timing, and recognized assets and liabilities. This table does not include leveraged buyouts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1486-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Period Type:	duration