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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Subsequent Events (Details) $ in Millions	Oct. 01, 2016	Dec. 31, 2016 USD ($)	Nov. 30, 2016 subsidiary
Air Products \| Forecast \| Pension Plan
Subsequent Event [Line Items]
Net benefit obligation \| $		$ 24
Subsequent Event
Subsequent Event [Line Items]
Amount of additional fees due over cost (as percent)	5.00%
Subsequent Event \| Minimum
Subsequent Event [Line Items]
Transition services agreement term	12 months
Subsequent Event \| Maximum
Subsequent Event [Line Items]
Transition services agreement term	24 months
Subsequent Event \| Air Products
Subsequent Event [Line Items]
Stock split conversion ratio	0.5
Number of Subsidiaries In Agreement \| subsidiary			1