Consolidated Statements of Stockholders' Deficit Parentheticals - shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Exercise of stock options, net (in shares)	3,044
Employee stock purchase plan sales, net (in shares)	260	321	246
Issuance of common stock, net (in shares)		3,846	22,044
Warrants issued (in shares)			3,511
Warrants exercised (in shares)	253
Common Stock
Exercise of stock options, net (in shares)		3,299	510
Employee stock purchase plan sales, net (in shares)	260	321	246