CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019
Stockholders' equity:
Convertible preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001
Convertible preferred stock, authorized shares	5,000,000	5,000,000	5,000,000	5,000,000	5,000,000	5,000,000
Convertible preferred stock, issued shares	0	0	0	0	0	0
Convertible preferred stock, outstanding shares	0	0	0	0	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001	$ 0.001
Common stock, authorized shares	500,000,000	500,000,000	500,000,000	500,000,000	500,000,000	500,000,000
Common stock, issued shares	111,697,994	113,922,520	113,743,652	113,275,229	112,131,352	111,493,448
Common stock, outstanding shares	111,697,994	113,922,520	113,743,652	113,275,229	112,131,352	111,493,448

Face amount or stated value per share of common stock.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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