Note 8. Credit Facilities - Primary Credit Facility Textuals (Details) - Primary Credit Facility $ in Millions	12 Months Ended
	Jun. 30, 2021 USD ($)
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
Minimum
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Line of Credit Facility, Eurocurrency Loans Spread	0.01250
Line of Credit Facility, Alternate Base Rate Loans Spread	0.00250
Maximum
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Line of Credit Facility, Eurocurrency Loans Spread	0.01750
Line of Credit Facility, Alternate Base Rate Loans Spread	0.00750