Related Party Transactions - Additional Information (Detail)	3 Months Ended	6 Months Ended
Sep. 30, 2020 USD ($) shares	Sep. 30, 2020 USD ($) shares
Nimble Holding Company Limited
Related Party Transaction [Line Items]
Nimble's Ownership Interest in Emerson number of shares \| shares	15,243,283	15,243,283
Nimble's Ownership Interest Percentage	72.40%	72.40%
VACL
Related Party Transaction [Line Items]
Advanced payment of rental and utility fees from related parties	$ 43,000	$ 86,000
Due from related parties	0	0
LSSL
Related Party Transaction [Line Items]
Due from related parties	0	0
Air conditioning installation charges due	$ 2,000	$ 2,600

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Name Accounting Standards Codification
-Topic 210
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Name:	us-gaap_DueFromRelatedPartiesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant