3. Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Basic Numerator:
Net loss attributable to Acacia Research Corporation	$ (11,291)	$ (4,384)
Dividend on Series A redeemable convertible preferred stock	(263)	0
Accretion of Series A Redeemable Convertible Preferred Stock	(631)	0
Net loss attributable to common stockholders - basic	$ (12,185)	$ (4,384)
Basic Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders - basic and diluted	49,875,396	49,655,881
Basic and diluted net loss per share of common stock	$ (0.24)	$ (0.09)