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Balance Sheet Details - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Apr. 22, 2020	Dec. 31, 2019
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 40,000		$ 909,000
Inventory, net	6,013,000		2,211,000
Inventory reserves	900,000		100,000
Proceeds from disposal of tenant improvements and certain equipment	3,070,000
Promissory Note \| Paycheck Protection Program (PPP Loan)
Restricted Cash And Cash Equivalents Items [Line Items]
Promissory note		$ 2,300,000
Debt instrument, interest rate		1.00%
Tetraphase Pharmaceuticals, Inc. \| Fair Value Step-Up Adjustment to Inventory
Restricted Cash And Cash Equivalents Items [Line Items]
Inventory, net	900,000
San Diego Lease
Restricted Cash And Cash Equivalents Items [Line Items]
Loss on termination of lease	13,000,000.0
Proceeds from disposal of tenant improvements and certain equipment	3,100,000
Credit Card
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 40,000
Standby Letters of Credit \| San Diego Lease
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash			$ 900,000