Property and Equipment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 29, 2018	Dec. 30, 2017	Mar. 31, 2018
Property and equipment, net
Land and improvements	$ 15.3		$ 15.3		$ 16.8
Buildings and improvements	390.3		390.3		460.5
Furniture and fixtures	665.9		665.9		671.0
Machinery and equipment	412.1		412.1		430.4
Capitalized software	580.6		580.6		578.4
Leasehold improvements	1,224.6		1,224.6		1,181.2
Construction in progress	37.3		37.3		41.5
Property and equipment, gross	3,326.1		3,326.1		3,379.8
Less: accumulated depreciation	(2,246.8)		(2,246.8)		(2,193.5)
Property and equipment, net	1,079.3		1,079.3		$ 1,186.3
Operating costs and expenses
Depreciation expense	$ 66.0	$ 66.7	$ 194.3	$ 201.4

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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