Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net loss including noncontrolling interests	$ (17,129)	$ (104,848)
Other comprehensive income (loss):
Unrealized loss on foreign currency translation, net of tax of $0	0	88
Total other comprehensive loss	(17,129)	(104,760)
Comprehensive (income) loss attributable to noncontrolling interests	14	(181)
Comprehensive loss attributable to Acacia Research Corporation	$ (17,115)	$ (104,941)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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