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

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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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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No definition available.

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Subsequent Events - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Nov. 01, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Subsequent Event [Line Items]
Payments for monthly base rent		$ 2,700	$ 2,500	$ 5,300	$ 4,900
188 Spear Street, San Francisco, California \| Subsequent Event
Subsequent Event [Line Items]
Construction allowance	$ 2,600
188 Spear Street, San Francisco, California \| Minimum \| Subsequent Event
Subsequent Event [Line Items]
Payments for monthly base rent	480
188 Spear Street, San Francisco, California \| Maximum \| Subsequent Event
Subsequent Event [Line Items]
Payments for monthly base rent	$ 620