CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income for the period	$ 285,637	$ 242,300	$ 1,025,915
Other comprehensive income (loss)—net of tax:
Net foreign currency translation adjustments	(3,882)	(9,582)	(4,756)
Unrealized gain (loss) on cash flow hedges:
Unrealized gain (loss) - net of tax expense (recovery) effect of $6, ($171) and $34 for the year ended June 30, 2019, 2018 and 2017, respectively	16	(476)	95
(Gain) loss reclassified into net income - net of tax (expense) recovery effect of $539, ($489) and $67 for the year ended June 30, 2019, 2018 and 2017, respectively	1,494	(1,357)	186
Actuarial gain (loss) relating to defined benefit pension plans:
Actuarial gain (loss) - net of tax expense (recovery) effect of ($2,004), ($1,846) and $840 for the year ended June 30, 2019, 2018 and 2017, respectively	(7,421)	(3,383)	6,216
Amortization of actuarial (gain) loss into net income - net of tax (expense) recovery effect of $292, $183 and $241 for the year ended June 30, 2019, 2018 and 2017, respectively	272	260	565
Unrealized net gain (loss) on marketable securities - net of tax effect of nil for the year ended June 30, 2019, 2018 and 2017 respectively	0	0	184
Release of unrealized gain on marketable securities - net of tax effect of nil for the year ended June 30, 2019, 2018 and 2017 respectively	0	(617)	0
Total other comprehensive income (loss) net, for the period	(9,521)	(15,155)	2,490
Total comprehensive income	276,116	227,145	1,028,405
Comprehensive (income) loss attributable to non-controlling interests	(136)	(76)	(256)
Total comprehensive income attributable to OpenText	$ 275,980	$ 227,069	$ 1,028,149