Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	Jul. 31, 2018	Jul. 31, 2017
Level 2 \| Long-term Debt
Debt Instrument [Line Items]
Long-term debt, fair value	$ 263.3	$ 330.6
Long-term debt, carrying value	275.0	325.0
Level 3
Debt Instrument [Line Items]
Carrying value of equity method investments	$ 21.7	$ 19.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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