CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income for the period	$ 234,368,000	$ 285,637,000	$ 242,300,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of intangible assets	514,734,000	470,928,000	456,929,000
Share-based compensation expense	29,532,000	26,770,000	27,594,000
Pension expense	5,802,000	4,624,000	3,738,000
Amortization of debt issuance costs	4,633,000	4,330,000	4,646,000
Amortization of deferred charges and credits	0	0	4,242,000
Accelerated amortization of right of use assets (note 18)	36,864,000
Loss on extinguishment of debt	17,854,000	0	0
Loss on sale and write down of property and equipment	9,714,000	9,438,000	2,234,000
Release of unrealized gain on marketable securities to income	0	0	(841,000)
Deferred taxes	51,388,000	47,425,000	89,736,000
Share in net (income) loss of equity investees	(8,700,000)	(13,668,000)	(5,965,000)
Write off of unamortized debt issuance costs	0	0	155,000
Changes in operating assets and liabilities:
Accounts receivable	84,499,000	75,508,000	(22,566,000)
Contract assets	(40,301,000)	(37,623,000)	0
Prepaid expenses and other current assets	(6,897,000)	(819,000)	(7,274,000)
Income taxes and deferred charges and credits	(35,086,000)	27,291,000	(31,323,000)
Accounts payable and accrued liabilities	30,613,000	(21,732,000)	(91,650,000)
Deferred revenue	25,306,000	(1,827,000)	35,629,000
Other assets	1,127,000	(4,000)	497,000
Operating lease assets and liabilities, net	(914,000)
Net cash provided by operating activities	954,536,000	876,278,000	708,081,000
Cash flows from investing activities:
Additions of property and equipment	(72,709,000)	(63,837,000)	(105,318,000)
Other investing activities	(14,127,000)	(16,966,000)	(18,034,000)
Net cash used in investing activities	(1,469,417,000)	(464,526,000)	(444,441,000)
Cash flows from financing activities:
Proceeds from issuance of Common Shares from exercise of stock options and ESPP	66,600,000	57,889,000	75,935,000
Proceeds from long-term debt and Revolver	3,150,000,000	0	1,200,000,000
Repayment of long-term debt and Revolver	(1,713,631,000)	(10,000,000)	(1,149,620,000)
Debt extinguishment costs (note 23)	(11,248,000)	0	0
Debt issuance costs	(21,806,000)	(322,000)	(4,375,000)
Purchase of Treasury Stock	(12,424,000)	(26,499,000)	0
Purchase of non-controlling interests	0	(583,000)	0
Payments of dividends to shareholders	(188,712,000)	(168,859,000)	(145,613,000)
Net cash provided by (used in) financing activities	1,268,779,000	(148,374,000)	(23,673,000)
Foreign exchange gain (loss) on cash held in foreign currencies	(178,000)	(3,826,000)	(2,186,000)
Increase (decrease) in cash, cash equivalents and restricted cash during the period	753,720,000	259,552,000	237,781,000
Cash, cash equivalents and restricted cash at beginning of the period	943,543,000	683,991,000	446,210,000
Cash, cash equivalents and restricted cash at end of the period	1,697,263,000	943,543,000	683,991,000
Reconciliation of cash, cash equivalents and restricted cash:
Total cash, cash equivalents and restricted cash	1,697,263,000	683,991,000	683,991,000
XMedius
Cash flows from investing activities:
Purchase of business	(73,335,000)	0	0
Carbonite
Cash flows from investing activities:
Purchase of business	(1,305,097,000)	0	0
Dynamic Solutions Group
Cash flows from investing activities:
Purchase of business	(4,149,000)	0	0
Catalyst Repository Systems Inc
Cash flows from investing activities:
Purchase of business	0	(70,800,000)	0
Liaison Technologies Inc.
Cash flows from investing activities:
Purchase of business	0	(310,644,000)	0
Hightail
Cash flows from investing activities:
Purchase of business	0	0	(20,535,000)
Guidance Software Inc.
Cash flows from investing activities:
Purchase of business	0	(2,279,000)	(229,275,000)
Covisint Corporation
Cash flows from investing activities:
Purchase of business	$ 0	$ 0	$ (71,279,000)