The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902458&loc=d3e39896-112707

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- Definition

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.

+ References

No definition available.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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- Definition

The cash inflow from borrowing by the entity from developers, builders, government agencies and municipalities for construction that are repaid in cash, generally on a straight-line basis over periods ranging from five to forty years.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Nov. 01, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2017
Operating Leased Assets [Line Items]
Deferred rent		$ 8.9		$ 8.9		$ 9.2
Rent expense, net of sublease income, for operating leases		3.1	$ 2.4	8.4	$ 7.3
Purchase commitments		$ 24.7		$ 24.7		$ 29.9
188 Spear Street, San Francisco, California
Operating Leased Assets [Line Items]
Construction allowance	$ 2.6