INCOME/LOSS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net income (loss) attributable to Acacia Research Corporation	$ 28,090	$ 89,757	$ (106,679)	$ (55,048)
Dividend on Series A redeemable convertible preferred stock	(700)	(262)	(2,099)	(785)
Accretion of Series A redeemable convertible preferred stock	(1,337)	(991)	(3,729)	(2,762)
Undistributed earnings allocated to participating securities	(5,466)	(15,394)	0	0
Net income (loss) attributable to common stockholders - Basic	20,587	73,110	(112,507)	(58,595)
Less: Change in fair value of Series A warrants	(3,389)	63	0	0
Less: Change in fair value of dilutive Series B warrants	(21,766)	(902)	0	0
Add: Interest expense associated with Starboard Notes, net of tax	850	1,536	0	0
Add: Undistributed earnings allocated to participating securities	5,466	15,394	0	0
Reallocation of undistributed earnings to participating securities	(217)	(8,893)	0	0
Net income (loss) attributable to common stockholders - Diluted	$ 1,531	$ 80,308	$ (112,507)	$ (58,595)
Denominator:
Weighted average number of shares outstanding - Basic	38,052,426	48,949,504	42,830,700	48,759,873
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	71,164,236	93,081,502	42,830,700	48,759,873
Weighted average number of shares outstanding, diluted	71,164,236	93,081,502	42,830,700	48,759,873
Basic net income (loss) per common share (in usd per share)	$ 0.54	$ 1.49	$ (2.63)	$ (1.20)
Diluted net (loss) income per common share (in usd per share)	$ 0.02	$ 0.86	$ (2.63)	$ (1.20)
Anti-dilutive potential common shares excluded from the computation of diluted net income/loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	69,520,233	398,168	108,217,890	107,230,624
Restricted stock units
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	539,989	798,356	0	0
Stock options
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	18,397	35,815	0	0
Series A warrants
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	1,046,575	2,019,724	0	0
Series B warrants
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	31,506,849	41,278,103	0	0
Equity-based incentive awards
Anti-dilutive potential common shares excluded from the computation of diluted net income/loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	1,027,082	398,168	3,217,890	2,230,624
Series A warrants
Anti-dilutive potential common shares excluded from the computation of diluted net income/loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0	5,000,000	5,000,000
Series B warrants
Anti-dilutive potential common shares excluded from the computation of diluted net income/loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	68,493,151	0	100,000,000	100,000,000