Period of time which holders were prevented from transferring stock as part of an acquisition.

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Conversion ratio of exchangeable shares as part of an acquisition.

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No definition available.

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Number of shares of equity interests issued or issuable to acquire entity.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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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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No definition available.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Stockholders' Equity - Exchangeable Shares, Share Repurchase Program and Secondary Public Offering (Details) $ / shares in Units, shares in Millions, $ in Millions					12 Months Ended
	Sep. 09, 2019 $ / shares shares	Jun. 13, 2019 shares	Nov. 30, 2018 USD ($)	Jun. 01, 2018 shares	Apr. 30, 2019 USD ($) shares	Apr. 30, 2020 USD ($)
Exchangeable Shares and Share Repurchase Program
Number of shares repurchased					1.0
Shares repurchased, cost \| $					$ 16.5
Remaining amount under repurchase program \| $						$ 58.5
AEA Investors LP \| Selling Stockholders
Exchangeable Shares and Share Repurchase Program
Shares sold	6.8
Price to the public (in dollars per share) \| $ / shares	$ 27.20
Maximum
Exchangeable Shares and Share Repurchase Program
Shares repurchased, cost \| $			$ 75.0
Titan
Exchangeable Shares and Share Repurchase Program
Issuance of shares to current shareholders of Titan (in shares)				1.1
Exchangeable shares converted		1.1
Exchangeable shares conversion ratio				1
Duration which stock can not be transferred				1 year