Investments - Supplemental Employee Retirement Plan Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jun. 30, 2020
Schedule of Trading Securities and Other Trading Assets
Total SERP investments	$ 13,586	$ 11,975
Total SERP obligation	13,586	11,975
Short-term Investments
Schedule of Trading Securities and Other Trading Assets
Total SERP investments	3,463	3,622
Total SERP obligation	3,463	3,622
Other Long-term Investments
Schedule of Trading Securities and Other Trading Assets
Total SERP investments	10,123	8,353
Total SERP obligation	$ 10,123	$ 8,353

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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+ References

No definition available.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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