DEBT - Short-Term Debt (Details) - USD ($)	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Short-term Debt [Line Items]
Short-term debt	$ 4,200,000	$ 9,200,000
Weighted-average interest rate	3.30%	2.20%
Short-term Lines of Credit
Short-term Debt [Line Items]
Borrowing capacity	$ 113,500,000	$ 129,200,000
Short-term debt	2,300,000	4,700,000
Letter of credit
Short-term Debt [Line Items]
Undrawn letters of credit	6,300,000	5,400,000
Bank Guarantee
Short-term Debt [Line Items]
Undrawn letters of credit	$ 97,100,000	$ 59,800,000
Minimum | Short-term Lines of Credit
Short-term Debt [Line Items]
Interest rate spread	0.40%	0.20%
Maximum | Short-term Lines of Credit
Short-term Debt [Line Items]
Interest rate spread	7.30%	10.70%