Summary of Significant Accounting Policies - Additional Information (Detail)			3 Months Ended
	Mar. 31, 2020 USD ($)	Sep. 26, 2019	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Common stock, stock split description		1-for-20
Common stock reverse split ratio		0.05
Unbilled accounts receivable	$ 0		$ 0	$ 700,000
Excess or obsolete inventory	0
Restricted cash	699,000		699,000	699,000
Amount payable to landlord in respect of default on rental obligation	159,000		159,000
Field Force Corporate Credit Card Program [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	500,000		500,000
Letter of Credit [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	159,000		159,000
Corporate Credit Card [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	40,000		40,000
XERAVA [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable from customer	1,000,000		1,000,000	800,000
Account receivable from contract	$ 700,000		700,000	$ 700,000
Capitalized milestone payments			$ 4,750,000
Estimated useful lives			12 years
Amortization period			5 years
Amortization expense			$ 400,000