Loans and Allowance for Loan Losses - Credit Quality Indicators (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Financing Receivable, Credit Quality, Additional Information	lending relationships of $3 million or more, exclusive of any consumer or owner-occupied residential loan, are subject to an annual credit analysis which is prepared by the loan administration department and presented to a loan committee with appropriate lending authority. A sample of lending relationships in excess of $1 million (exclusive of single-family residential real estate loans) are subject to an independent loan review annually, in order to verify risk ratings.
Loans without a specific valuation allowance
Purchased Credit Impaired Loans	$ 21.8	$ 28.5

Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 29
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953659-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953664-111524

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