| Cover | Aug. 09, 2021 | Jul. 26, 2021 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Amendment Flag | false | |
| Document Period End Date | Aug. 9, 2021 | |
| Entity File Number | 001-15288 | |
| Entity Registrant Name | Network 1 Technologies, Inc. | |
| Entity Central Index Key | 0001065078 | |
| Entity Tax Identification Number | 11-3027591 | |
| Entity Incorporation, State or Country Code | DE | |
| Entity Address, Address Line One | 445 Park Avenue | |
| Entity Address, Address Line Two | Suite 912 | |
| Entity Address, City or Town | New York | |
| Entity Address, State or Province | NY | |
| Entity Address, Postal Zip Code | 10022 | |
| City Area Code | (212) | |
| Local Phone Number | 829-5770 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Title of 12(b) Security | Common Stock, par value $0.01 per share | |
| Trading Symbol | NTIP | |
| Security Exchange Name | NYSEAMER | |
| Entity Emerging Growth Company | false |
