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Note 3 - Loans and Allowance for Loan Losses - Retail Credit Exposure (Details) - USD ($) | Sep. 30, 2016 | Dec. 31, 2015 | Sep. 30, 2015
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Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 72,680,000 | $ 67,816,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | 74,835,000 | 55,255,000 |
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | 147,515,000 | 123,071,000 | $ 117,390,000
Originated Loan [Member] |  |  |
Loans | 1,873,221,000 | 1,616,587,000 | $ 1,519,710,000
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | 54,946,000 | 72,830,000 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | 115,880,000 | 135,130,000 |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | 170,826,000 | 207,960,000 |
Acquired Loan [Member] |  |  |
Loans | 533,156,000 | 661,140,000 |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | 127,626,000 | 140,646,000 |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | 190,715,000 | 190,385,000 |
Retail Portfolio Segment [Member] |  |  |
Loans | 318,341,000 | 331,031,000 |
Loans | $ 2,406,377,000 | $ 2,277,727,000 |

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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=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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