ALLOWANCE FOR CREDIT LOSSES (Allowance For Credit Losses By Segment, Class And Impairment Status) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	$ 24,837,000	$ 28,101,000
Allowance for impaired loans and leases	388,000	1,519,000
Allowance for all other loans and leases	136,272,000	140,924,000
Total allowance	136,660,000	142,443,000	149,704,000	153,236,000
Evaluated for impairment threshold	500,000
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	1,840,000	2,154,000
Allowance for impaired loans and leases	79,000	215,000
Allowance for all other loans and leases	20,942,000	21,204,000
Total allowance	21,021,000	21,419,000	18,914,000	18,376,000
Real Estate [Member] \| Consumer Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	3,165,000	4,786,000
Allowance for impaired loans and leases	123,000	123,000
Allowance for all other loans and leases	38,948,000	39,892,000
Total allowance	39,071,000	40,015,000	38,328,000	39,525,000
Real Estate [Member] \| Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	610,000	619,000
Allowance for impaired loans and leases	74,000	70,000
Allowance for all other loans and leases	9,472,000	9,472,000
Total allowance	9,546,000	9,542,000	5,712,000	5,663,000
Real Estate [Member] \| Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Allowance for all other loans and leases	3,146,000	3,420,000
Total allowance	3,146,000	3,420,000	2,834,000	2,800,000
Real Estate [Member] \| Commercial And Industrial - Owner Occupied [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	5,881,000	7,467,000
Allowance for impaired loans and leases	112,000	89,000
Allowance for all other loans and leases	15,552,000	16,236,000
Total allowance	15,664,000	16,325,000	16,561,000	17,059,000
Real Estate [Member] \| Construction, Acquisition And Development [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	3,160,000	2,387,000
Allowance for all other loans and leases	9,913,000	9,885,000
Total allowance	9,913,000	9,885,000	10,320,000	11,828,000
Real Estate [Member] \| Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	10,017,000	10,518,000
Allowance for impaired loans and leases		1,022,000
Allowance for all other loans and leases	21,502,000	22,540,000
Total allowance	21,502,000	23,562,000	44,771,000	43,853,000
Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Allowance for all other loans and leases	5,319,000	6,514,000
Total allowance	5,319,000	6,514,000	2,486,000	3,782,000
All Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded balance of impaired loans	164,000	170,000
Allowance for all other loans and leases	11,478,000	11,761,000
Total allowance	$ 11,478,000	$ 11,761,000	$ 9,778,000	$ 10,350,000

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=28368275&loc=SL6953423-111524

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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=28368275&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

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

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