PENSION PLANS AND OTHER POST RETIREMENT BENEFITS - Schedule of Weighted-Average Key Assumptions Used for Pension Plans (Details) - Pension Plan	3 Months Ended	12 Months Ended
Sep. 30, 2020	Jun. 30, 2020
CDT
Assumptions:
Salary increases	1.75%	1.75%
Pension increases	1.50%	1.50%
Discount rate	1.14%	1.46%
CDT \| to age 20
Assumptions:
Employee fluctuation rate	0.00%	0.00%
CDT \| to age 25
Assumptions:
Employee fluctuation rate	0.00%	0.00%
CDT \| to age 30
Assumptions:
Employee fluctuation rate	1.00%	1.00%
CDT \| to age 35
Assumptions:
Employee fluctuation rate	0.50%	0.50%
CDT \| to age 40
Assumptions:
Employee fluctuation rate	0.00%	0.00%
CDT \| to age 45
Assumptions:
Employee fluctuation rate	0.50%	0.50%
CDT \| to age 50
Assumptions:
Employee fluctuation rate	0.50%	0.50%
CDT \| from age 51
Assumptions:
Employee fluctuation rate	1.00%	1.00%
CDT \| Minimum
Assumptions:
Normal retirement age	65 years	65 years
CDT \| Maximum
Assumptions:
Normal retirement age	67 years	67 years
GXS GER
Assumptions:
Salary increases	2.50%	2.50%
Pension increases	2.00%	2.00%
Discount rate	1.14%	1.46%
GXS GER \| to age 20
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 25
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 30
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 35
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 40
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 45
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| to age 50
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| from age 51
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS GER \| Minimum
Assumptions:
Normal retirement age	65 years	65 years
GXS GER \| Maximum
Assumptions:
Normal retirement age	67 years	67 years
GXS PHP
Assumptions:
Salary increases	6.50%	6.50%
Discount rate	3.90%	3.50%
Normal retirement age	60 years	60 years
GXS PHP \| to age 20
Assumptions:
Employee fluctuation rate	12.19%	12.19%
GXS PHP \| to age 25
Assumptions:
Employee fluctuation rate	16.58%	16.58%
GXS PHP \| to age 30
Assumptions:
Employee fluctuation rate	13.97%	13.97%
GXS PHP \| to age 35
Assumptions:
Employee fluctuation rate	10.77%	10.77%
GXS PHP \| to age 40
Assumptions:
Employee fluctuation rate	7.39%	7.39%
GXS PHP \| to age 45
Assumptions:
Employee fluctuation rate	3.28%	3.28%
GXS PHP \| to age 50
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS PHP \| from age 51
Assumptions:
Employee fluctuation rate	0.00%	0.00%

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Rate Of Pension Increase

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Retirement Age

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- Definition

Employee Fluctuation Rate

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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