Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Series A Redeemable Convertible Preferred Stock	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Deficit	Noncontrolling Interests in Operating Subsidiaries	Total
Beginning balance, shares at Dec. 31, 2018		49,639,319
Beginning balance, value at Dec. 31, 2018		$ 50	$ (39,272)	$ 651,156	$ (422,541)	$ 1,847	$ 191,240
Net loss attributable to Acacia Research Corporation					(17,115)		(17,115)
Accretion of Series A redeemable convertible preferred stock to redemption value	$ 307			(307)			(307)
Stock options exercised, shares		25,136
Stock options exercised, value				79			79
Compensation expense for share-based awards, net of forfeitures, shares		706,532
Compensation expense for share-based awards, net of forfeitures, value				1,075			1,075
Distributions to noncontrolling interests in subsidiaries							0
Issuance of Series A Redeemable Convertible Preferred Shares, net of embedded derivative, Series A Warrant, and issuance costs, shares	350,000
Issuance of Series A Redeemable Convertible Preferred Shares, net of embedded derivative, Series A Warrant, and issuance costs, value	$ 7,782
Net income (loss) attributable to noncontrolling interests in subsidiaries						(14)	(14)
Ending balance, shares at Dec. 31, 2019	350,000	50,370,987
Ending balance, value at Dec. 31, 2019	$ 8,089	$ 50	(39,272)	652,003	(439,656)	1,833	174,958
Net loss attributable to Acacia Research Corporation					113,444		113,444
Accretion of Series A redeemable convertible preferred stock to redemption value	2,835			(2,835)			(2,835)
Dividend on Series A Redeemable Convertible Preferred Stock				(1,382)			(1,382)
Stock options exercised, shares
Stock options exercised, value				48			48
Compensation expense for share-based awards, net of forfeitures, shares		593,003
Compensation expense for share-based awards, net of forfeitures, value				1,662			1,662
Repurchase of common stock, shares		(1,684,537)
Repurchase of common stock, value		$ (1)	(3,998)				(3,999)
Dissolution of Acacia Intellectual Property Fund, L.P.				1,920	(496)	(1,424)
Distributions to noncontrolling interests in subsidiaries						(409)	(409)
Acquisition of MalinJ1						11,042	11,042
Net income (loss) attributable to noncontrolling interests in subsidiaries							0
Ending balance, shares at Dec. 31, 2020	350,000	49,279,453
Ending balance, value at Dec. 31, 2020	$ 10,924	$ 49	$ (43,270)	$ 651,416	$ (326,708)	$ 11,042	$ 292,529