Note 12. Investments - Supplemental Employee Retirement Plan Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020
Schedule of Trading Securities and Other Trading Assets
SERP investments	$ 12,708	$ 11,975
SERP obligation	12,708	11,975
Short-term Investments
Schedule of Trading Securities and Other Trading Assets
SERP investments	3,861	3,622
SERP obligation	3,861	3,622
Other Long-term Investments
Schedule of Trading Securities and Other Trading Assets
SERP investments	8,847	8,353
SERP obligation	$ 8,847	$ 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.

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-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
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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).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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