Pension Plans and Other Post Retirement Benefits - Schedule of Weighted-Average Key Assumptions Used for Pension Plans (Details) - Pension Plan	6 Months Ended	12 Months Ended
Dec. 31, 2017	Jun. 30, 2017
CDT
Assumptions:
Salary increases	2.00%	2.00%
Pension increases	1.75%	1.75%
Discount rate	1.93%	2.00%
Normal retirement age	65 years	65 years
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%
GXS Germany
Assumptions:
Salary increases	2.00%	2.00%
Pension increases	2.00%	2.00%
Discount rate	1.93%	2.00%
GXS Germany \| to age 20
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 25
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 30
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 35
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 40
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 45
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| to age 50
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| from age 51
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Germany \| Minimum
Assumptions:
Normal retirement age	65 years	65 years
GXS Germany \| Maximum
Assumptions:
Normal retirement age	67 years	67 years
GXS Philippines
Assumptions:
Salary increases	6.20%	6.20%
Discount rate	5.75%	5.00%
Normal retirement age	60 years	60 years
GXS Philippines \| to age 20
Assumptions:
Employee fluctuation rate	12.19%	12.19%
GXS Philippines \| to age 25
Assumptions:
Employee fluctuation rate	16.58%	16.58%
GXS Philippines \| to age 30
Assumptions:
Employee fluctuation rate	13.97%	13.97%
GXS Philippines \| to age 35
Assumptions:
Employee fluctuation rate	10.77%	10.77%
GXS Philippines \| to age 40
Assumptions:
Employee fluctuation rate	7.39%	7.39%
GXS Philippines \| to age 45
Assumptions:
Employee fluctuation rate	3.28%	3.28%
GXS Philippines \| to age 50
Assumptions:
Employee fluctuation rate	0.00%	0.00%
GXS Philippines \| 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=82843861&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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