ALLOWANCE FOR CREDIT LOSSES (Allowance For Credit Losses By Segment, Class And Impairment Status) (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	$ 28,258,000	$ 38,237,000
Allowance for impaired loans and leases		4,353,000
Evaluated for impairment threshold	500,000
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	7,562,000	8,314,000
Allowance for impaired loans and leases	1,190,000	1,837,000
Allowance for all other loans and leases	14,939,000	17,333,000
Total allowance	16,129,000	19,170,000	$ 17,719,000	$ 17,583,000
Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Allowance for all other loans and leases	6,345,000	7,787,000
Total allowance	6,345,000	7,787,000	3,439,000	4,047,000
All Other [Member]
Financing Receivable, Impaired [Line Items]
Allowance for all other loans and leases	7,307,000	5,346,000
Total allowance	7,307,000	5,346,000	6,156,000	6,117,000
Consumer Mortgages [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	2,424,000	1,655,000
Allowance for impaired loans and leases	554,000
Allowance for all other loans and leases	32,990,000	30,386,000
Total allowance	33,544,000	30,386,000	33,225,000	33,198,000
Home Equity [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	850,000	857,000
Allowance for impaired loans and leases	30,000
Allowance for all other loans and leases	6,930,000	7,174,000
Total allowance	6,960,000	7,174,000	7,167,000	6,949,000
Agricultural [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	5,245,000	861,000
Allowance for all other loans and leases	1,851,000	2,172,000
Total allowance	1,851,000	2,172,000	2,363,000	2,524,000
Commercial And Industrial - Owner Occupied [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	7,210,000	8,321,000
Allowance for all other loans and leases	12,790,000	12,899,000
Total allowance	12,790,000	12,899,000	13,642,000	14,607,000
Construction, Acquisition And Development [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	246,000	5,933,000
Allowance for impaired loans and leases		35,000
Allowance for all other loans and leases	13,532,000	13,922,000
Total allowance	13,532,000	13,957,000	15,536,000	15,925,000
Commercial Real Estate [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	4,721,000	12,296,000
Allowance for impaired loans and leases	112,000	2,481,000
Allowance for all other loans and leases	22,991,000	22,364,000
Total allowance	$ 23,103,000	$ 24,845,000	$ 27,688,000	$ 25,508,000

Amount of allowance for credit losses related to non-impaired loans and leases.

No definition available.

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- Definition

This element represents the aggregate carrying amount of all cost-method investments held by the Entity which was not evaluated for impairment. Because the fair value of cost-method investments is not readily determinable, the evaluation of whether an investment is impaired generally consists of whether an event or change in circumstances has occurred during the reporting period that may have a significant adverse effect on the fair value of the investment (an "impairment indicator"). Impairment indicators include, but are not limited to: (1) significant deterioration in the earnings performance, credit rating, asset quality, or business prospects of the investee; (2) significant adverse change in the regulatory, economic, or technological environment of the investee; (3) significant adverse change in the general market condition of either the geographic area or the industry in which the investee operates; (4) a bona fide offer to purchase (whether solicited or unsolicited), an offer by the investee to sell, or a completed auction process for the same or similar security for an amount less than the cost of the investment; or (5) factors that raise significant concerns about the investee's ability to continue as a going concern, such as negative cash flows from operations, working capital deficiencies, or noncompliance with statutory capital requirements or debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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