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

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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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Amount remaining of a stock repurchase plan authorized.

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- Definition

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

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- Definition

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 and Share Repurchase Program (Details) - USD ($) shares in Millions, $ in Millions			9 Months Ended
	Nov. 30, 2018	Jun. 01, 2018	Jan. 31, 2019
Exchangeable Shares and Share Repurchase Program
Number of shares repurchased			0.7
Shares repurchased, cost			$ 11.5
Remaining amount under repurchase program			$ 63.5
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