CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
Cash flows from operating activities
Net income	$ 22.1	$ 23.3
Adjustments to reconcile net income/(loss) to net cash provided by operating activities
Depreciation and amortization	167.8	183.8
Loss on extinguishment of debt		4.9
Gain on sale of SRT	(5.5)
Non-cash interest expense	2.5	2.4
Stock-based compensation	26.7	27.8
Amortization of deferred revenue	(37.0)	(32.4)
Foreign currency (gain)/loss on intercompany loans	4.6	(10.8)
Deferred income taxes	15.9	2.7
Provision for bad debts	1.5	0.8
Non-cash loss on investments	0.3	0.1
Changes in operating assets and liabilities, net of acquisitions
Trade receivables	4.5	(32.0)
Accounts payable and accrued liabilities	9.0	53.4
Additions to deferred revenue	30.5	40.5
Other assets and liabilities	(1.1)	4.3
Net cash provided by operating activities	241.8	268.8
Cash flows from investing activities
Purchases of property and equipment	(182.5)	(193.4)
Proceeds from sale of SRT, net of cash held in escrow	39.0
Net cash used in investing activities	(143.5)	(193.4)
Cash flows from financing activities
Proceeds from debt		312.8
Principal payments on long-term debt	(1.3)	(311.9)
Principal payments on capital lease obligations	(1.9)	(1.7)
Payment of debt issuance costs		(3.4)
Common stock repurchases	(0.2)
Cash paid for Santa Clara acquisition financing arrangement and other	(3.3)	(1.3)
Net cash provided by financing activities	(6.7)	(5.5)
Net cash flows	91.6	69.9
Effect of changes in foreign exchange rates on cash	2.2	0.6
Net increase in cash, cash equivalents and restricted cash	93.8	70.5
Cash, cash equivalents and restricted cash, beginning of year	261.3	225.2	$ 225.2
Cash, cash equivalents and restricted cash, end of period	355.1	295.7	261.3
Supplemental disclosure of non-cash investing and financing activities:
Cash paid for interest, net of capitalized interest	63.4	54.3
Cash paid for income taxes	2.0	1.4
Non-cash purchases of equipment through capital leasing	21.9	0.1
Non-cash purchases of equipment through nonmonetary exchange	31.1	1.5
(Decrease)/increase in accounts payable and accrued expenses for purchases of property and equipment	(2.4)	(18.0)
Cash and cash equivalents				$ 353.9	$ 256.7	$ 291.2	$ 220.7
Restricted cash included in other assets				1.2	4.6	4.5	4.5
Total cash, cash equivalents and restricted cash	$ 261.3	$ 225.2	$ 225.2	$ 355.1	$ 261.3	$ 295.7	$ 225.2