Funding Arrangements (Details) - USD ($)	1 Months Ended		8 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2016	Oct. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
CARB-X program
Funding Arrangements
Grant income recognized				$ 2,300,000	$ 4,800,000
Funds received during the period				2,600,000	3,800,000
Grants receivable				1,200,000	1,500,000
USAMRAA grant
Funding Arrangements
Maximum reimbursable research expenditures		$ 1,100,000
Grant income recognized				37,000	500,000
Funds received during the period				200,000	900,000
Grants receivable				$ 0	$ 200,000
Maximum | CARB-X program
Funding Arrangements
Maximum reimbursable research expenditures	$ 16,800,000		$ 16,400,000