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Note 10 - Fair Values of Financial Instruments - Fair Value Hierarchy of Financial Instruments (Details) - USD ($)

Mar. 31, 2018

Dec. 31, 2017

Debt Securities, Available-for-sale, Total

$ 336,988,000

$ 335,744,000

Reported Value Measurement [Member]

Debt Securities, Available-for-sale, Total

^[1]

336,988,000

335,744,000

FHLBI stock

^[2]

11,036,000

11,036,000

Repurchase agreements

104,894,000

118,748,000

FHLBI advances

220,000,000

220,000,000

Reported Value Measurement [Member] | Interest Rate Swap [Member]

Interest rate swap

^[1]

0

2,000

Estimate of Fair Value Measurement [Member]

Debt Securities, Available-for-sale, Total

^[1]

336,988,000

335,744,000

FHLBI stock

^[2]

11,036,000

11,036,000

Repurchase agreements

104,894,000

118,748,000

FHLBI advances

214,172,000

217,130,000

Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member]

Interest rate swap

^[1]

0

2,000

Fair Value, Inputs, Level 1 [Member] | Reported Value Measurement [Member]

Cash

11,148,000

11,565,000

Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]

Cash

11,148,000

11,565,000

Fair Value, Inputs, Level 2 [Member] | Reported Value Measurement [Member]

Cash equivalents

200,009,000

188,536,000

Loans held for sale

1,864,000

2,553,000

Mortgage servicing rights

4,899,000

5,106,000

Accrued interest receivable

9,590,000

8,770,000

Deposits

2,540,053,000

2,522,365,000

Subordinated debentures

45,688,000

45,517,000

Accrued interest payable

2,172,000

1,919,000

Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]

Cash equivalents

200,009,000

188,536,000

Loans held for sale

1,864,000

2,553,000

Mortgage servicing rights

8,223,000

8,373,000

Accrued interest receivable

9,590,000

8,770,000

Deposits

2,361,212,000

2,368,188,000

Subordinated debentures

46,280,000

45,732,000

Accrued interest payable

2,172,000

1,919,000

Fair Value, Inputs, Level 3 [Member] | Reported Value Measurement [Member]

Loans, net

2,529,366,000

2,536,498,000

Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]

Loans, net

$ 2,528,622,000

$ 2,520,063,000

[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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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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