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Note 4 - Loans and Allowance for Loan Losses - Activity in Allowance for Loan Losses and the Recorded Investments in Loans (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Provision for loan losses | $ 2,900,000 | $ (1,000,000) | $ (3,000,000)
Loans | 2,378,620,000 | 2,277,727,000 |
Commercial Portfolio Segment [Member] |  |  |
Loans | 2,065,347,000 | 1,946,696,000 |
Retail Portfolio Segment [Member] |  |  |
Loans | 313,273,000 | 331,031,000 |
Originated Loan [Member] |  |  |
Beginning balance | 15,233,000 | 19,299,000 | 22,821,000
Provision for loan losses | 3,098,000 | (701,000) | (3,793,000)
Charge-offs | (2,133,000) | (6,195,000) | (1,430,000)
Recoveries | 1,670,000 | 2,830,000 | 1,701,000
Ending balance | 17,868,000 | 15,233,000 | 19,299,000
Ending balance: individually evaluated for impairment | 1,572,000 | 1,474,000 | 10,152,000
Ending balance: collectively evaluated for impairment | 16,296,000 | 13,759,000 | 9,147,000
Loans | 1,884,548,000 | 1,616,587,000 | 1,246,116,000
Ending balance: individually evaluated for impairment | 13,383,000 | 18,197,000 | 47,856,000
Ending balance: collectively evaluated for impairment | 1,871,165,000 | 1,598,390,000 | 1,198,260,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Beginning balance | 13,672,000 | 17,736,000 | 20,455,000
Provision for loan losses | 2,247,000 | (1,771,000) | (3,140,000)
Charge-offs | (980,000) | (4,915,000) | (876,000)
Recoveries | 1,087,000 | 2,622,000 | 1,297,000
Ending balance | 16,026,000 | 13,672,000 | 17,736,000
Ending balance: individually evaluated for impairment | 1,303,000 | 1,218,000 | 9,374,000
Ending balance: collectively evaluated for impairment | 14,723,000 | 12,454,000 | 8,362,000
Loans | 1,728,898,000 | 1,493,516,000 | 1,153,189,000
Ending balance: individually evaluated for impairment | 12,070,000 | 16,845,000 | 45,021,000
Ending balance: collectively evaluated for impairment | 1,716,828,000 | 1,476,671,000 | 1,108,168,000
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Beginning balance | 1,421,000 | 1,487,000 | 2,358,000
Provision for loan losses | 1,031,000 | 1,006,000 | (721,000)
Charge-offs | (1,153,000) | (1,280,000) | (554,000)
Recoveries | 583,000 | 208,000 | 404,000
Ending balance | 1,882,000 | 1,421,000 | 1,487,000
Ending balance: individually evaluated for impairment | 269,000 | 256,000 | 778,000
Ending balance: collectively evaluated for impairment | 1,613,000 | 1,165,000 | 709,000
Loans | 155,650,000 | 123,071,000 | 92,927,000
Ending balance: individually evaluated for impairment | 1,313,000 | 1,352,000 | 2,835,000
Ending balance: collectively evaluated for impairment | 154,337,000 | 121,719,000 | 90,092,000
Originated Loan [Member] | Unallocated Financing Receivables [Member] |  |  |
Beginning balance | 140,000 | 76,000 | 8,000
Provision for loan losses | (180,000) | 64,000 | 68,000
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Ending balance | (40,000) | 140,000 | 76,000
Ending balance: individually evaluated for impairment | 0 | 0 | 0
Ending balance: collectively evaluated for impairment | (40,000) | 140,000 | 76,000
Acquired Loan [Member] |  |  |
Beginning balance | 448,000 | 742,000 | 0
Provision for loan losses | (198,000) | (299,000) | 793,000
Charge-offs | (72,000) | (84,000) | (71,000)
Recoveries | (85,000) | 89,000 | 20,000
Ending balance | 93,000 | 448,000 | 742,000
Loans | 494,072,000 | 661,140,000 |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Beginning balance | 420,000 | 738,000 | 0
Provision for loan losses | (303,000) | (286,000) | 791,000
Charge-offs | 0 | (77,000) | (55,000)
Recoveries | (42,000) | 45,000 | 2,000
Ending balance | 75,000 | 420,000 | 738,000
Loans | 336,449,000 | 453,180,000 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Beginning balance | 28,000 | 4,000 | 0
Provision for loan losses | 105,000 | (13,000) | 2,000
Charge-offs | (72,000) | (7,000) | (16,000)
Recoveries | (43,000) | 44,000 | 18,000
Ending balance | 18,000 | 28,000 | 4,000
Loans | 157,623,000 | 207,960,000 |
Acquired Loan [Member] | Unallocated Financing Receivables [Member] |  |  |
Beginning balance | 0 | 0 | 0
Provision for loan losses | 0 | 0 | 0
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Ending balance | $ 0 | $ 0 | $ 0

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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 + Details
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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + 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 (g) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + 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 (g) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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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=65884687&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=66008989&loc=d3e5074-111524 + Details
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