Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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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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Equity-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
	Mar. 06, 2019	Aug. 03, 2019	Aug. 04, 2018	Aug. 03, 2019	Aug. 04, 2018	May 04, 2019	Apr. 01, 2019	Mar. 19, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity based compensation expense		$ 1.2	$ 1.0	$ 2.4	$ 1.8
Special cash dividend, per share	$ 1.15					$ 1.15
Cash dividend paid							$ 50.2
Dividend declared, date	Mar. 06, 2019
Dividend payable, date	Apr. 01, 2019
Shareholders of record, date	Mar. 19, 2019
2017 Plan [Member] \| Restricted Share Awards ("RSAs") [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Special cash dividend, per share								$ 1.15