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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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- 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 + Details
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