Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 30, 2020	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Fair Value Measurements
Contingent consideration expense		$ 1,800	$ 800
Impairment of goodwill	$ 63,100	63,074
Impairment charges	1,900	0	0	$ 0
Fair Value, Measurements, Recurring \| Level 3
Fair Value Measurements
Stock appreciation rights	24,205	24,205	23,458
Deferred compensation	1,660	1,660	1,695
Noncontrolling interest holders	8,300	8,300	12,498
Contingent consideration			12,354
Interest rate swap agreements \| Fair Value, Measurements, Recurring \| Level 2
Fair Value Measurements
Derivative liabilities	32,218	32,218	$ 5,613
Titan
Fair Value Measurements
Assumed contingent consideration arrangements	$ 12,400	$ 12,400

The amount of expense related to a contingent consideration arrangement during the reporting period.

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- Definition

Contingent Consideration Fair Value Disclosure

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- Definition

Fair value portion of deferred compensation.

+ References

No definition available.

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- Definition

Fair value portion of noncontrolling interest holders.

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- Definition

Fair value portion of stock appreciation rights.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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