INCOME TAXES - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Taxes
Other income tax rate reconciling items (as a percent)	2.00%	6.20%	(2.50%)
Rate impact of meals and entertainment expense disallowance (as a percent)		4.50%
Rate impact of charitable contributions (as a percent)		7.10%
Rate impact of miscellaneous items (as a percent)		(5.40%)
Tax act, provisional income tax benefit	$ 68.1
Tax act, release of valuation allowance	30.5
Tax act, tax benefit for deferred tax remeasurement	37.6
Tax credit carryforward amount subject to expiration	35.1
Undistributed earnings of international subsidiaries	14.5
Reserve on unrecognized tax benefits that would benefit the effective tax rate	2.4
Interest and penalties	0.1	$ 0.1	$ 0.1
Accrued interest and penalties related to unrecognized tax benefits	1.2
Expiring from 2030 to 2038
Income Taxes
Tax credit carryforward amount subject to expiration	33.1
Expiring from 2020 to 2028
Income Taxes
Tax credit carryforward amount subject to expiration	0.5
Tax Credit Carryforward, Without Expiration
Income Taxes
Tax credit carryforward amount subject to expiration	1.5
Domestic Tax Authority
Income Taxes
Operating loss carryforwards	28.2
State Tax Authority
Income Taxes
Operating loss carryforwards	12.7
Foreign Tax Authority | Canada Revenue Agency
Income Taxes
Operating loss carryforwards	0.5
Foreign Tax Authority | Her Majesty's Revenue and Customs (HMRC)
Income Taxes
Operating loss carryforwards	$ 0.2