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Balance Sheet Details - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Apr. 22, 2020
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 40,000	$ 909,000
Inventory, net	5,374,000		$ 6,013,000
Inventory reserves	1,100,000		900,000
Amortization expense	388,000	$ 0
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	0		900,000
Credit Card
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 40,000		$ 40,000