Pension Plans and Other Post Retirement Benefits - Schedule of the Change in Benefit Obligation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation—beginning of period	$ 61,520	$ 55,536	$ 55,536
Service cost	660		2,409
Interest cost	289		1,467
Benefits paid	(333)		(1,494)
Actuarial (gain) loss	(945)		4,718
Foreign exchange (gain) loss	767		(1,116)
Benefit obligation—end of period	61,958		61,520
Less: Current portion	(1,493)		(1,391)
Non-current portion of benefit obligation	60,465		60,129
Pension Plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	660	637
Interest cost	289	363
Pension Plan \| CDT
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation—beginning of period	29,450	26,091	26,091
Service cost	120	107	422
Interest cost	117	154	610
Benefits paid	(118)		(534)
Actuarial (gain) loss	1,266		3,299
Foreign exchange (gain) loss	501		(438)
Benefit obligation—end of period	31,336		29,450
Less: Current portion	(610)		(589)
Non-current portion of benefit obligation	30,726		28,861
Pension Plan \| GXS Germany
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation—beginning of period	24,729	22,420	22,420
Service cost	101	103	359
Interest cost	96	128	543
Benefits paid	(205)		(770)
Actuarial (gain) loss	1,294		2,564
Foreign exchange (gain) loss	438		(387)
Benefit obligation—end of period	26,453		24,729
Less: Current portion	(811)		(772)
Non-current portion of benefit obligation	25,642		23,957
Pension Plan \| GXS Philippines
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation—beginning of period	7,341	7,025	7,025
Service cost	439	427	1,628
Interest cost	76	$ 81	314
Benefits paid	(10)		(190)
Actuarial (gain) loss	(3,505)		(1,145)
Foreign exchange (gain) loss	(172)		(291)
Benefit obligation—end of period	4,169		7,341
Less: Current portion	(72)		(30)
Non-current portion of benefit obligation	$ 4,097		$ 7,311

This represents the current liability recognized in the balance sheet that is associated with the defined benefit pension plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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