Retirement and Post-Retirement Benefit Plans (Details) - Defined Benefit Plans $ in Billions	3 Months Ended
Oct. 31, 2017 USD ($)
Defined benefit plans
Plan assets	$ 8.3
Projected benefit obligation	8.1
Recognized accumulated comprehensive loss	$ 1.9

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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