Employee Benefit Plans (Unfunded Commitments and Redemption Restrictions) (Details) - Pension Plan - U.S. Plan - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Measured Using NAV Per Share as Practical Expedient	$ 70.3	$ 72.3
Unfunded Commitments	6.1
Global equity securities
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Measured Using NAV Per Share as Practical Expedient	40.5	35.8
Unfunded Commitments	$ 1.8
Global equity securities \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Redemption Notice Period	10 days
Global equity securities \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Redemption Notice Period	90 days
Private equity and other funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Measured Using NAV Per Share as Practical Expedient	$ 26.8	33.1
Unfunded Commitments	$ 0.0
Private equity and other funds \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Redemption Notice Period	60 days
Private equity and other funds \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Redemption Notice Period	90 days
Real asset funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share
Measured Using NAV Per Share as Practical Expedient	$ 3.0	$ 3.4
Unfunded Commitments	$ 4.3

Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets

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- Definition

Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258

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