Note 8. Credit Facilities - Primary and Secondary Credit Facility Textuals (Details) $ in Millions	12 Months Ended
	Jun. 30, 2020 USD ($)
Primary Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity	$ 150
Line of Credit Facility, Maximum Borrowing Capacity Upon Request	$ 225
Line of Credit Facility, Above the Adjusted LIBOR Rate to Calculate Alternate Base Rate	1.00%
Line of Credit Facility, Above the Federal Funds Rate to Calculate Alternate Base Rate	0.50%
Adjusted Leverage Ratio, Indebtedness Reduction For Excess Cash	$ 15
Adjusted Leverage Ratio Covenant	3.0
Fixed Charge Coverage Ratio Covenant	1.10
Secondary Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity	$ 30
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.50%
Line of Credit Facility, Eurocurrency Loans Spread	0.02125
Line of Credit Facility, Above the Adjusted LIBOR Rate to Calculate Alternate Base Rate	1.00%
Line of Credit Facility, Above the Federal Funds Rate to Calculate Alternate Base Rate	0.50%
Line of Credit Facility, Alternate Base Rate Loans Spread	0.01125
Adjusted Leverage Ratio, Indebtedness Reduction For Excess Cash	$ 15
Adjusted Leverage Ratio Covenant	3.0
Fixed Charge Coverage Ratio Covenant	1.10
Minimum | Primary Credit Facility
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Line of Credit Facility, Eurocurrency Loans Spread	0.0125
Line of Credit Facility, Alternate Base Rate Loans Spread	0.0025
Maximum | Primary Credit Facility
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Line of Credit Facility, Eurocurrency Loans Spread	0.0175
Line of Credit Facility, Alternate Base Rate Loans Spread	0.0075