STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (27,371)	$ (24,528)	$ (23,598)	$ (11,813)	$ (51,899)	$ (35,411)
Adjustments to reconcile net loss to net cash used in operations:
Stock-based compensation					3,046	2,907
Net amortization of premium on investments					1,396	2
Depreciation					1,134	557
Tangible Asset Impairment Charges	400				400	0
Non-cash operating lease expense					141	0
Changes in operating assets and liabilities:
Prepaid expenses and other current assets					4,285	(890)
Other assets					13	18
Accounts payable					(4,522)	(903)
Accrued expenses and other current liabilities					3,539	3,974
Non-current operating lease liabilities					(337)	0
Deferred revenue					211	2,959
Deferred rent					0	1,380
Net cash used in operating activities					(42,593)	(25,407)
Cash flows from investing activities:
Purchase of property and equipment					(10,171)	(4,972)
Net change in investments					(1,778)	(42,312)
Net cash used in investing activities					(11,949)	(47,284)
Cash flows from financing activities:
Proceeds from the exercise of stock options and purchases pursuant to employee stock purchase plan					144	1,287
Net cash provided by financing activities					144	1,287
Net decrease in cash and cash equivalents					(54,398)	(71,404)
Cash and cash equivalents, beginning of period		$ 92,268		$ 157,898	92,268	157,898	$ 157,898
Cash and cash equivalents, end of period	$ 37,870		$ 86,494		37,870	86,494	$ 92,268
Supplemental disclosures of non-cash financial activities:
Operating lease liabilities recognized for operating right-of-use assets					5,447	0
Operating right-of-use assets exchanged for operating lease liabilities					2,945	0
Unpaid amounts related to purchases of property and equipment					$ 184	$ 156