Investment Securities - Narrative (Details)	12 Months Ended
Dec. 31, 2015 USD ($) security	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Fair value of investments	$ 177,584,000	$ 72,390,000
Unrealized losses on mortgage-backed securities portfolio	578,000	250,000
Unrealized losses in available for sale and held to maturity portfolios	802,000	608,000
Carrying value of securities pledged as collateral	637,358,000	449,408,000	$ 373,533,000
Gross gains on securities sold	2,770,000	3,581,000	487,000
Gross losses from sale of available for sale securities	100,000	0	$ 0
Investments in Debt and Equity Securities, Reported at Less than Historical Cost
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Historical cost	178,964,000	73,249,000
Fair value of investments	$ 177,584,000	$ 72,390,000
Percent of the Corporation's available for sale and held to maturity portfolio	13.90%	6.10%
U.S. Government-Sponsored Mortgage-backed Securities
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Unrealized losses on mortgage-backed securities portfolio	$ 518,000	$ 127,000
Available-for-sale, number of securities in unrealized loss positions \| security	26
Unrealized losses in available for sale and held to maturity portfolios	$ 787,000	512,000
Held-to-maturity, number of securities in unrealized loss positions \| security	22
State and Municipal Securities
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Unrealized losses on mortgage-backed securities portfolio	$ 60,000	123,000
Available-for-sale, number of securities in unrealized loss positions \| security	22
Unrealized losses in available for sale and held to maturity portfolios	$ 15,000	$ 96,000
Held-to-maturity, number of securities in unrealized loss positions \| security	7
Merger with Ameriana Bancorp
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
Percentage of interest acquired	100.00%
Investment securities acquired	$ 60,365,000

Investment Historical Cost

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Percentage of Total Investment Portfolio, Fair Value

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Schedule of Available for sale Securities and Held to maturity Securities [Line Items]

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Securities, Continuous Unrealized Loss Position, Fair Value

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Securities Pledged as Collateral

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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-Name Accounting Standards Codification
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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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