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v3.20.2

Investments - Additional Information (Detail) | 6 Months Ended
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Sep. 30, 2020
Minimum [Member] |
Schedule of Held-to-maturity Securities [Line Items] |
Treasury with original maturities period | 3 months
Maximum [Member] |
Schedule of Held-to-maturity Securities [Line Items] |
Investment maturity date range end | Dec. 24, 2020
Treasury with original maturities period | 1 year

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- Definition Original maturity period for held to maturity securities. + References No definition available. + Details
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- Definition Maturity date of investment, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
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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. + Details
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- Details
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