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Note 4 - Loans and Allowance for Loan Losses (Details) - Activity in Allowance for Loan Losses and the Recorded Investments in Loans - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for loan losses | $ (1,000,000) | $ (3,000,000) | $ (7,200,000)
Total loans: |  |  |
Loans | 2,277,727,000 | 2,089,277,000 |
Originated Loan [Member] |  |  |
Total loans: |  |  |
Loans | 1,616,587,000 |  |
Loans: individually evaluated for impairment | 18,197,000 |  |
Loans: collectively evaluated for impairment | 1,598,390,000 |  |
Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 19,299,000 | 22,821,000 | 28,677,000
Provision for loan losses | (701,000) | (3,793,000) | (7,200,000)
Charge-offs | (6,195,000) | (1,430,000) | (5,290,000)
Recoveries | 2,830,000 | 1,701,000 | 6,634,000
Allowance for loan losses | 15,233,000 | 19,299,000 | 22,821,000
Allowance for loan losses: individually evaluated for impairment | 1,474,000 | 10,152,000 | 12,386,000
Allowance for loan losses: collectively evaluated for impairment | 13,759,000 | 9,147,000 | 10,435,000
Total loans: |  |  |
Loans | 1,616,587,000 | 1,246,116,000 | 1,053,243,000
Loans: individually evaluated for impairment |  | 47,856,000 | 36,868,000
Loans: collectively evaluated for impairment |  | 1,198,260,000 | 1,016,375,000
Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 742,000 | 0 |
Provision for loan losses | (299,000) | 793,000 |
Charge-offs | (84,000) | (71,000) |
Recoveries | 89,000 | 20,000 |
Allowance for loan losses | 448,000 | 742,000 | 0
Total loans: |  |  |
Loans | 661,140,000 | 843,161,000 |
Commercial Portfolio Segment [Member] |  |  |
Total loans: |  |  |
Loans | 1,946,696,000 | 1,715,303,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Total loans: |  |  |
Loans | 1,493,516,000 |  |
Loans: individually evaluated for impairment | 16,845,000 |  |
Loans: collectively evaluated for impairment | 1,476,671,000 |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 17,736,000 | 20,455,000 | 26,043,000
Provision for loan losses | (1,771,000) | (3,140,000) | (6,730,000)
Charge-offs | (4,915,000) | (876,000) | (5,120,000)
Recoveries | 2,622,000 | 1,297,000 | 6,262,000
Allowance for loan losses | 13,672,000 | 17,736,000 | 20,455,000
Allowance for loan losses: individually evaluated for impairment | 1,218,000 | 9,374,000 | 11,260,000
Allowance for loan losses: collectively evaluated for impairment | 12,454,000 | 8,362,000 | 9,195,000
Total loans: |  |  |
Loans | 1,493,516,000 | 1,153,189,000 | 986,696,000
Loans: individually evaluated for impairment |  | 45,021,000 | 33,240,000
Loans: collectively evaluated for impairment |  | 1,108,168,000 | 953,456,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 681,000 | 0 |
Provision for loan losses | (617,000) | 734,000 |
Charge-offs | (77,000) | (55,000) |
Recoveries | 45,000 | 2,000 |
Allowance for loan losses | 32,000 | 681,000 | 0
Total loans: |  |  |
Loans | 453,180,000 | 562,114,000 |
Retail Portfolio Segment [Member] |  |  |
Total loans: |  |  |
Loans | 331,031,000 | 373,974,000 |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Total loans: |  |  |
Loans | 123,071,000 |  |
Loans: individually evaluated for impairment | 1,352,000 |  |
Loans: collectively evaluated for impairment | 121,719,000 |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 1,487,000 | 2,358,000 | 2,645,000
Provision for loan losses | 1,006,000 | (721,000) | (489,000)
Charge-offs | (1,280,000) | (554,000) | (170,000)
Recoveries | 208,000 | 404,000 | 372,000
Allowance for loan losses | 1,421,000 | 1,487,000 | 2,358,000
Allowance for loan losses: individually evaluated for impairment | 256,000 | 778,000 | 1,126,000
Allowance for loan losses: collectively evaluated for impairment | 1,165,000 | 709,000 | 1,232,000
Total loans: |  |  |
Loans | 123,071,000 | 92,927,000 | 66,547,000
Loans: individually evaluated for impairment |  | 2,835,000 | 3,628,000
Loans: collectively evaluated for impairment |  | 90,092,000 | 62,919,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 61,000 | 0 |
Provision for loan losses | 318,000 | 59,000 |
Charge-offs | (7,000) | (16,000) |
Recoveries | 44,000 | 18,000 |
Allowance for loan losses | 416,000 | 61,000 | 0
Total loans: |  |  |
Loans | 207,960,000 | 281,047,000 |
Unallocated Financing Receivables [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 76,000 | 8,000 | (11,000)
Provision for loan losses | 64,000 | 68,000 | 19,000
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Allowance for loan losses | 140,000 | 76,000 | 8,000
Allowance for loan losses: individually evaluated for impairment | 0 | 0 | 0
Allowance for loan losses: collectively evaluated for impairment | 140,000 | 76,000 | 8,000
Unallocated Financing Receivables [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Allowance for loan losses | 0 | 0 |
Provision for loan losses | 0 | 0 |
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Allowance for loan losses | $ 0 | $ 0 | $ 0

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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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