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Note 4 - Loans and Allowance for Loan Losses (Details) - Retail Credit Risk by Collateral Type - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 2,277,727,000	$ 2,089,277,000
Originated Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,616,587,000	1,246,116,000	$ 1,053,243,000
Acquired Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	661,140,000	843,161,000
Retail Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	331,031,000	373,974,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	140,646,000	159,278,000
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	190,385,000	214,696,000
Retail Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	123,071,000	92,927,000	$ 66,547,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	67,816,000	50,059,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	55,255,000	42,868,000
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	207,960,000	281,047,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	72,830,000	109,219,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 135,130,000	$ 171,828,000

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+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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