Redeemable Convertible Preferred Stock - Schedule of Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2020
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	106,090,000	0
Redeemable convertible preferred stock,Shares issued	52,435,000	0
Redeemable convertible preferred stock,Shares outstanding	52,435,000	0
Liquidation preference	$ 280,513
Gross proceeds	$ 280,513
Series A
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	5,400,000
Redeemable convertible preferred stock,Shares issued	2,700,000
Redeemable convertible preferred stock,Shares outstanding	2,700,000
Liquidation preference	$ 2,106
Gross proceeds	$ 2,106
Series B
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	21,733,000
Redeemable convertible preferred stock,Shares issued	10,815,000
Redeemable convertible preferred stock,Shares outstanding	10,815,000
Liquidation preference	$ 15,790
Gross proceeds	$ 15,790
Series C
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	9,197,000
Redeemable convertible preferred stock,Shares issued	4,599,000
Redeemable convertible preferred stock,Shares outstanding	4,599,000
Liquidation preference	$ 8,500
Gross proceeds	$ 8,500
Series D
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	12,425,000
Redeemable convertible preferred stock,Shares issued	6,200,000
Redeemable convertible preferred stock,Shares outstanding	6,200,000
Liquidation preference	$ 15,500
Gross proceeds	$ 15,500
Series E
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	17,512,000
Redeemable convertible preferred stock,Shares issued	8,756,000
Redeemable convertible preferred stock,Shares outstanding	8,756,000
Liquidation preference	$ 35,200
Gross proceeds	$ 35,200
Series E-1
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	1,393,000
Redeemable convertible preferred stock,Shares issued	697,000
Redeemable convertible preferred stock,Shares outstanding	697,000
Liquidation preference	$ 2,800
Gross proceeds	$ 2,800
Series F
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	9,756,000
Redeemable convertible preferred stock,Shares issued	4,878,000
Redeemable convertible preferred stock,Shares outstanding	4,878,000
Liquidation preference	$ 29,750
Gross proceeds	$ 29,750
Series F-1
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	82,000
Redeemable convertible preferred stock,Shares issued	41,000
Redeemable convertible preferred stock,Shares outstanding	41,000
Liquidation preference	$ 250
Gross proceeds	$ 250
Series G
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	16,892,000
Redeemable convertible preferred stock,Shares issued	8,446,000
Redeemable convertible preferred stock,Shares outstanding	8,446,000
Liquidation preference	$ 82,500
Gross proceeds	$ 82,500
Series H
Schedule Of Stockholders Equity [Line Items]
Redeemable convertible preferred stock,Shares authorized	11,700,000
Redeemable convertible preferred stock,Shares issued	5,303,000
Redeemable convertible preferred stock,Shares outstanding	5,303,000
Liquidation preference	$ 88,117
Gross proceeds	$ 88,117

Proceeds From Issuance Of Convertible Preferred Stock Gross

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Schedule Of Stockholders Equity [Line Items]

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Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(d))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27)(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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