Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities
Net loss	$ (95,407)	$ (54,397)
Adjustments to reconcile net income to net cash used in operating activities:
Stock-based compensation expense	20,136	15,638
Depreciation and amortization expense	2,318	2,528
Premium paid on marketable securities	(846)	(3,427)
Amortization of premium on marketable securities	1,118	1,516
Change in operating assets and liabilities:
Accounts receivable	4,097	1,868
Prepaid expenses and other current assets	2,648	1,518
Income tax receivable	8,527	(17,529)
Operating lease, right-of-use assets	3,932	4,019
Accounts payable	(8,555)	195
Accrued expenses	(3,253)	3,671
Operating lease liabilities	(3,235)	(4,343)
Other long-term assets	(611)	0
Other long-term liabilities	(117)	(232)
Net cash used in operating activities	(69,248)	(48,975)
Cash flows from investing activities
Purchase of marketable securities	(162,714)	(307,949)
Proceeds from maturities and sale of marketable securities	190,068	272,974
Purchase of property and equipment	(688)	(717)
Net cash provided by (used in) investing activities	26,666	(35,692)
Cash flows from financing activities
Proceeds from exercise of stock options	18,331	2,671
Payments for settlement of share-based awards	(1,228)	(534)
Net cash provided by financing activities	17,103	2,137
Net decrease in cash, cash equivalents and restricted cash	(25,479)	(82,530)
Cash, cash equivalents and restricted cash at beginning of period	57,814	87,739
Cash, cash equivalents and restricted cash at end of period	32,335	5,209
Supplemental disclosure of non-cash operating and investing information:
Purchases of fixed assets included in accounts payable and accrued expenses	412	16
Operating lease liabilities arising from obtaining right-of-use assets	$ 22,984	$ 3,057