Leases - Lease expense and supplemental cash flow information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2019	Dec. 31, 2019
Leases [Abstract]
Operating lease expense	$ 12,879	$ 24,830
Short-term lease cost	2,109	4,434
Variable lease cost	1,685	2,959
Total lease cost	16,673	32,223
Cash paid for amounts included in the measurement of operating lease liabilities	12,732	24,582
Right-of-use assets obtained in exchange for operating lease obligations	$ 8,730	$ 25,947