Acquisition Activity - Schedule of Acquired Loans (Details) - HF Financial Corp $ in Thousands	May 16, 2016 USD ($)
Business Acquisition [Line Items]
Fair Value of Acquired Loans at Acquisition Date	$ 812,209
Gross Contractual Amounts Receivable at Acquisition Date	998,255
Best Estimate at Acquisition Date of Contractual Cash Flows Not Expected to be Collected	9,572
Receivables acquired with deteriorated credit quality
Business Acquisition [Line Items]
Fair Value of Acquired Loans at Acquisition Date	51,532
Gross Contractual Amounts Receivable at Acquisition Date	83,710
Best Estimate at Acquisition Date of Contractual Cash Flows Not Expected to be Collected	$ 28,516

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No definition available.

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the best estimate at the acquisition date of the contractual cash flows not expected to be collected, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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