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Note 10 - Fair Values of Financial Instruments - Fair Value Hierarchy of Financial Instruments (Details) - USD ($) | Jun. 30, 2016 | Dec. 31, 2015
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Fair Value, Inputs, Level 1 [Member] | Reported Value Measurement [Member] |  |  |
Cash |  | $ 12,406,000 | $ 12,496,000
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member] |  |  |
Cash |  | 12,406,000 | 12,496,000
Fair Value, Inputs, Level 1 [Member] |  |  |
Available-for-sale Securities |  | 0 |
Fair Value, Inputs, Level 2 [Member] | Reported Value Measurement [Member] |  |  |
Cash equivalents |  | 94,577,000 | 77,395,000
Loans held for sale |  | 2,879,000 | 1,316,000
Bank owned life insurance |  | 66,537,000 | 58,971,000
Accrued interest receivable |  | 7,268,000 | 7,836,000
Deposits |  | 2,279,718,000 | 2,275,382,000
Repurchase agreements |  | 136,690,000 | 154,771,000
FHLBI advances |  | 178,000,000 | 68,000,000
Subordinated debentures |  | 44,494,000 | 55,154,000
Accrued interest payable |  | 1,517 | 1,479
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member] |  |  |
Cash equivalents |  | 94,577,000 | 77,395,000
Loans held for sale |  | 2,879,000 | 1,316,000
Bank owned life insurance |  | 66,537,000 | 58,971,000
Accrued interest receivable |  | 7,268,000 | 7,836,000
Deposits |  | 2,226,310,000 | 2,208,724,000
Repurchase agreements |  | 136,690,000 | 154,771,000
FHLBI advances |  | 180,504,000 | 68,858,000
Subordinated debentures |  | 44,505,000 | 55,760,000
Accrued interest payable |  | 1,517 | 1,479
Fair Value, Inputs, Level 3 [Member] | Reported Value Measurement [Member] |  |  |
Loans, net |  | 2,359,951,000 | 2,260,730,000
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member] |  |  |
Loans, net |  | 2,356,483,000 | 2,259,710,000
Reported Value Measurement [Member] | Interest Rate Swap [Member] |  |  |
Interest rate swap | [1] | 278,000 | 253,000
Reported Value Measurement [Member] |  |  |
Available-for-sale Securities | [1] | 323,452,000 | 346,992,000
FHLBI stock | [2] | 8,026,000 | 7,567,000
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member] |  |  |
Interest rate swap | [1] | 278,000 | 253,000
Estimate of Fair Value Measurement [Member] |  |  |
Available-for-sale Securities | [1] | 323,452,000 | 346,992,000
FHLBI stock | [2] | 8,026,000 | 7,567,000
Available-for-sale Securities |  | $ 323,452,000 | $ 346,992,000
[1] | See Note 11 for a description of the fair value hierarchy as well as a disclosure of levels for classes of financial assets and liabilities.
[2] | It is not practical to determine the fair value of FHLBI stock due to transferability restrictions.

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
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