Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

	Quarter Ended
	March 31,			June 30,			September 30,			December 31,
2019
Revenue	$	79,891		$	15,715		$	19,940		$	34,502
Net income (loss)		17,435			(51,867	)		(46,277	)		(30,851	)
Net income (loss) attributable to Agenus Inc. common shareholders		18,454			(50,686	)		(45,526	)		(30,107	)
Per common share, basic and diluted:
Basic net income (loss) attributable to Agenus Inc.    common stockholders		0.14			(0.38	)		(0.33	)		(0.22	)
Diluted net income (loss) attributable to Agenus Inc.    common stockholders		0.12			(0.38	)		(0.33	)		(0.22	)
2018
Revenue	$	1,636		$	15,895		$	12,802		$	6,451
Net loss		(54,261	)		(25,204	)		(33,731	)		(48,848	)
Net loss attributable to Agenus Inc. common shareholders		(54,192	)		(24,723	)		(33,177	)		(47,807	)
Per common share, basic and diluted:
Basic and diluted net loss attributable to Agenus Inc.    common stockholders		(0.53	)		(0.24	)		(0.37	)		(0.40	)