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Note 6 - Mortgage Loan Servicing (Tables) | 12 Months Ended
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Dec. 31, 2015
Mortgage Loan Servicing [Abstract] |
Mortgage Loans Serviced For Others [Table Text Block] |
|  | 2015 |  |  | 2014 |
Mortgage loan portfolios serviced for: |  |  |  |  |  |  |  |
Federal Home Loan Mortgage Corporation |  | $ | 598,510,000 |  |  | $ | 589,118,000 |
Federal Home Loan Bank |  |  | 4,675,000 |  |  |  | 1,702,000 |
Total mortgage loans serviced for others |  | $ | 603,185,000 |  |  | $ | 590,820,000 |
Schedule of Servicing Assets at Fair Value [Table Text Block] |
|  | 2015 |  |  | 2014 |
Balance at beginning of year |  | $ | 6,712,000 |  |  | $ | 0 |
Additions |  |  | 1,487,000 |  |  |  | 575,000 |
Amortized to expense |  |  | (2,078,000 | ) |  |  | (1,252,000 | )
Firstbank merger |  |  | 0 |  |  |  | 7,389,000 |
Balance at end of year |  | $ | 6,121,000 |  |  | $ | 6,712,000 |
Servicing Asset at Amortized Cost [Table Text Block] |
2016 |  | $ | 1,409,000 |
2017 |  |  | 1,146,000 |
2018 |  |  | 955,000 |
2019 |  |  | 804,000 |
2020 |  |  | 659,000 |
Thereafter |  |  | 1,148,000 |

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- Definition Tabular disclosure on mortgage loan portfolios serviced for others. + References No definition available. + Details
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- Definition Tabular disclosure of activity in the balance of servicing assets subsequently measured at amortized cost. Includes, but is not limited to, beginning and ending balances, additions, disposals, and amortization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746 + Details
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- Definition Tabular disclosure of the activity in the balance of servicing assets (including a description of where changes in fair value are reported in the statement of income for each period for which results of operations are presented), including but not limited to, the following: beginning and ending balances, additions (for instance, through purchases of servicing assets), disposals, changes in fair value during the period resulting from changes in inputs or assumptions used in the valuation model, other changes in fair value along with a description of those changes, and other changes that affect the balance along with a description of those changes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122625-111746 + Details
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