INCOME/LOSS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net income (loss) attributable to Acacia Research Corporation	$ 1,636	$ 28,090	$ (7,696)	$ (106,679)
Dividend on Series A redeemable convertible preferred stock	0	(700)	(1,400)	(2,099)
Accretion of Series A redeemable convertible preferred stock	0	(1,337)	(3,230)	(3,729)
Undistributed earnings allocated to participating securities	0	(5,466)	0	0
Net (loss) income attributable to common stockholders - Basic	(1,740)	20,587	(15,703)	(112,507)
Add: Dividend on Series A redeemable convertible preferred stock	0	0	0	0
Less: Change in fair value of Series A warrants	0	(3,389)	0	0
Less: Change in fair value of dilutive Series B warrants	0	(21,766)	0	0
Add: Interest expense associated with Starboard Notes, net of tax	102	850	0	0
Add: Undistributed earnings allocated to participating securities	0	5,466	0	0
Reallocation of undistributed earnings to participating securities	0	(217)	0	0
Net (loss) income attributable to common stockholders - Diluted	$ (3,163)	$ 1,531	$ (15,703)	$ (112,507)
Denominator:
Weighted average number of shares outstanding - Basic	94,328,452	38,052,426	67,072,835	42,830,700
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	99,122,973	71,164,236	67,072,835	42,830,700
Weighted average number of shares outstanding, diluted	99,122,973	71,164,236	67,072,835	42,830,700
Basic net income (loss) per common share (in usd per share)	$ (0.02)	$ 0.54	$ (0.23)	$ (2.63)
Diluted net (loss) income per common share (in usd per share)	$ (0.03)	$ 0.02	$ (0.23)	$ (2.63)
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)	3,894,709	69,520,233	36,212,989	108,217,890
Add: Accretion of Series A redeemable convertible preferred stock	$ 0	$ 0	$ 0	$ 0
Less: Change in fair value of Series A redeemable convertible preferred stock embedded derivative	$ 0	$ 0	$ 0	$ 0
Restricted stock units
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	0	539,989	0	0
Stock options
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	0	18,397	0	0
Series A warrants
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	0	1,046,575	0	0
Series B warrants
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	4,794,521	31,506,849	0	0
Series A Redeemable Convertible Preferred Stock
Potentially dilutive common shares:
Potentially dilutive common shares (in shares)	0	0	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)	3,894,709	1,027,082	4,706,140	3,217,890
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	0	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)	0	68,493,151	31,506,849	100,000,000