FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Summarized Financial Data (Details) - USD ($) $ in Thousands	6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance Sheet Information
Current assets			$ 313,673		$ 342,058
Current liabilities			5,807		6,110
Income Statement Information
Total revenue			391,866		336,794	$ 261,016
Loss from operations			375,103		321,123	246,360
Net loss			$ 368,837		$ 293,814	$ 190,993
Armata
Balance Sheet Information
Current assets	$ 17,024	$ 17,024		$ 14,178
Noncurrent assets	28,651	28,651		28,493
Current liabilities	7,070	7,070		5,254
Noncurrent liabilities	13,986	13,986		13,662
Income Statement Information
Total revenue		319		3,989
Loss from operations		(15,134)		(24,227)
Net loss		(15,557)		(23,732)
Entasis
Balance Sheet Information
Current assets	68,398	68,398		49,746
Noncurrent assets	1,564	1,564		1,020
Current liabilities	6,862	6,862		9,348
Noncurrent liabilities	864	$ 864		183
Income Statement Information
Loss from operations	(26,080)			(52,323)
Net loss	$ (24,529)			$ (125,413)