Investments - Additional Information (Detail) |
6 Months Ended |
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Sep. 30, 2017 | |
| 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 | May 15, 2018 |
| Treasury with original maturities period | 1 year |
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- Definition Original maturity period for held to maturity securities. No definition available.
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- Definition Date of maturity of a debt security categorized as held-to-maturity, in CCYY-MM-DD format. No definition available.
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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. No definition available.
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- Details
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- Details
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