Leases - Components of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Operating lease expense	$ 1.3	$ 0.9	$ 3.1	$ 2.5
Variable lease expense	1.2	0.6	2.5	1.8
Total lease expense	$ 2.5	$ 1.5	$ 5.6	$ 4.3