Acquisitions - Narrative (Details) - Ameriana $ in Thousands, shares in Millions	Dec. 31, 2015 USD ($) bank shares
Business Acquisition [Line Items]
Percentage of interest acquired	100.00%
Number of banking centers acquired \| bank	13
Stock issued as a part of acquisition (in shares) \| shares	2.8
Less: Common stock issued	$ 70,400
Core deposit intangible	$ 5,342
Acquired intangible asset, expected useful life	10 years
Common Stock
Business Acquisition [Line Items]
Number of shares of common stock	0.9037

Business Combinations, Acquiree, Shares of Stock Received For Each Share Currently Owned

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The number of businesses acquired by the entity during the period.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Value of stock issued pursuant to acquisitions during the period.

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