| Document and Entity Information | Feb. 16, 2024 |
| Cover [Abstract] | |
| Entity Registrant Name | ACACIA RESEARCH CORP |
| Amendment Flag | false |
| Entity Central Index Key | 0000934549 |
| Document Type | 8-K |
| Document Period End Date | Feb. 16, 2024 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-37721 |
| Entity Tax Identification Number | 95-4405754 |
| Entity Address, Address Line One | 767 Third Avenue |
| Entity Address, Address Line Two | 6th Floor |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10017 |
| City Area Code | (332) |
| Local Phone Number | 236-8500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, par value $0.001 per share |
| Trading Symbol | ACTG |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
