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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Summary of Significant Accounting Policies (Details) $ in Thousands		3 Months Ended	6 Months Ended
	May 01, 2019 USD ($) shares	Mar. 31, 2020 segment	Jun. 30, 2019 USD ($)
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of operating segments \| segment		1
Number of reportable segments \| segment		1
MidWestOne Insurance Services Inc
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Gain on disposition of business			$ 1,100
ATBancorp
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares issued (in shares) \| shares	4,117,536
Value of equity interest issued	$ 116,032
Cash consideration	$ 34,766