Acquisitions and Preliminary Purchase Price Allocation Acquisitions and Preliminary Purchase Price Allocation Goodwill Rollforward (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2018	$ 109,567
Balance at March 31, 2019	108,977
Poage Bankshares, Inc.
Goodwill [Roll Forward]
Adjustment to goodwill acquired	(529)
Balance at March 31, 2019	28,100
Farmers Deposit Bancorp, Inc.
Goodwill [Roll Forward]
Adjustment to goodwill acquired	(61)
Balance at March 31, 2019	$ 4,700

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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