PENSION PLANS AND OTHER POST RETIREMENT BENEFITS - Schedule of Defined Benefit Plans and Long-Term Employee Benefit Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Assumptions:
Total benefit obligation	$ 75,816	$ 77,531
Current portion of benefit obligation	2,687	2,292
Non-current portion of benefit obligation	73,129	75,239
Pension Plan | CDT defined benefit plan
Assumptions:
Total benefit obligation	32,851	35,836
Current portion of benefit obligation	777	675
Non-current portion of benefit obligation	32,074	35,161
Pension Plan | GXS GER defined benefit plan
Assumptions:
Total benefit obligation	24,105	26,739
Current portion of benefit obligation	943	1,012
Non-current portion of benefit obligation	23,162	25,727
Pension Plan | GXS PHP defined benefit plan
Assumptions:
Total benefit obligation	10,270	6,904
Current portion of benefit obligation	115	124
Non-current portion of benefit obligation	10,155	6,780
Other plans
Assumptions:
Total benefit obligation	8,590	8,052
Current portion of benefit obligation	852	481
Non-current portion of benefit obligation	$ 7,738	$ 7,571