Short-Term Investments - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 512,580,000		$ 512,580,000		$ 123,395,000
Short-term investments mature within one year	$ 284,400,000		$ 284,400,000		$ 102,900,000
Percentage of short-term investments maturing within one year	55.00%		55.00%		83.00%
Short-term investments mature thereafter	$ 228,100,000		$ 228,100,000		$ 21,100,000
Percentage of short-term investments maturing thereafter	45.00%		45.00%		17.00%
Short-term investments realized gains or losses	$ 0	$ 0	$ 0	$ 0
Accrued Interest Receivable
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	1,700,000		1,700,000		$ 500,000
Fair value	$ 1,700,000		$ 1,700,000		$ 500,000

Available for sale securities debt maturities after one year fair value.

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Percentage of debt securities available for sale maturing after one year.

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Percentage of debt securities available for sale maturing within one year.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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.

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