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Note 3 - Loans and Allowance for Loan Losses (Details) - Activity in Allowance for Loan Losses and the Recorded Investments in Loans - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Provision for loan losses | $ 600,000 | $ (400,000) |
Ending balance | 2,295,668,000 |  | $ 2,277,727,000
Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 15,233,000 | 19,299,000 |
Ending balance | 15,972,000 | 20,251,000 |
Allowance for loan losses: individually evaluated for impairment | 1,088,000 | 10,366,000 |
Allowance for loan losses: collectively evaluated for impairment | 14,884,000 | 9,885,000 |
Provision for loan losses | 671,000 | (457,000) |
Charge-offs | (475,000) | (441,000) |
Recoveries | 543,000 | 1,850,000 |
Ending balance | 1,687,476,000 | 1,328,713,000 | 1,616,587,000
Loans: individually evaluated for impairment | 17,729,000 | 45,450,000 |
Loans: collectively evaluated for impairment | 1,669,747,000 | 1,283,263,000 |
Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 448,000 | 742,000 |
Ending balance | 290,000 | 799,000 |
Provision for loan losses | (71,000) | 57,000 |
Charge-offs | 0 | (7,000) |
Recoveries | (87,000) | 7,000 |
Ending balance | 608,192,000 |  | 661,140,000
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Ending balance | 1,974,450,000 |  | 1,946,696,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 13,672,000 | 17,736,000 |
Ending balance | 13,924,000 | 18,977,000 |
Allowance for loan losses: individually evaluated for impairment | 913,000 | 10,158,000 |
Allowance for loan losses: collectively evaluated for impairment | 13,011,000 | 8,819,000 |
Provision for loan losses | 94,000 | (499,000) |
Charge-offs | (89,000) | (78,000) |
Recoveries | 247,000 | 1,818,000 |
Ending balance | 1,562,777,000 | 1,230,841,000 | 1,493,516,000
Loans: individually evaluated for impairment | 16,551,000 | 44,257,000 |
Loans: collectively evaluated for impairment | 1,546,226,000 | 1,186,584,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 420,000 | 681,000 |
Ending balance | 266,000 | 622,000 |
Provision for loan losses | (110,000) | (60,000) |
Charge-offs | 0 | 0 |
Recoveries | (44,000) | 1,000 |
Ending balance | 411,673,000 |  | 453,180,000
Retail Portfolio Segment [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Ending balance | 321,218,000 |  | 331,031,000
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 1,421,000 | 1,487,000 |
Ending balance | 1,834,000 | 1,235,000 |
Allowance for loan losses: individually evaluated for impairment | 175,000 | 208,000 |
Allowance for loan losses: collectively evaluated for impairment | 1,659,000 | 1,027,000 |
Provision for loan losses | 503,000 | 79,000 |
Charge-offs | (386,000) | (363,000) |
Recoveries | 296,000 | 32,000 |
Ending balance | 124,699,000 | 97,872,000 | 123,071,000
Loans: individually evaluated for impairment | 1,178,000 | 1,193,000 |
Loans: collectively evaluated for impairment | 123,521,000 | 96,679,000 |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 28,000 | 61,000 |
Ending balance | 24,000 | 177,000 |
Provision for loan losses | 39,000 | 117,000 |
Charge-offs | 0 | (7,000) |
Recoveries | (43,000) | 6,000 |
Ending balance | 196,519,000 |  | $ 207,960,000
Unallocated Financing Receivables [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 140,000 | 76,000 |
Ending balance | 214,000 | 39,000 |
Allowance for loan losses: individually evaluated for impairment | 0 | 0 |
Allowance for loan losses: collectively evaluated for impairment | 214,000 | 39,000 |
Provision for loan losses | 74,000 | (37,000) |
Charge-offs | 0 | 0 |
Recoveries | 0 | 0 |
Unallocated Financing Receivables [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Beginning balance | 0 | 0 |
Ending balance | 0 | 0 |
Provision for loan losses | 0 | 0 |
Charge-offs | 0 | 0 |
Recoveries | $ 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 of recovery of financing receivables doubtful of collection that were previously charged off. + 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)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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- Definition Amount of direct write-downs of financing receivables charged against the allowance. + 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)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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- Definition The balance of financing receivables 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 (h) -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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