| Document and Entity Information | Sep. 30, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | Energous Corp |
| Entity Address, State or Province | CA |
| Amendment Flag | false |
| Entity Central Index Key | 0001575793 |
| Document Type | 8-K |
| Document Period End Date | Sep. 30, 2020 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-36379 |
| Entity Tax Identification Number | 46-1318953 |
| Entity Address, Address Line One | 3590 North First Street |
| Entity Address, Address Line Two | Suite 210 |
| Entity Address, City or Town | San Jose |
| Entity Address, Postal Zip Code | 95134 |
| City Area Code | (408) |
| Local Phone Number | 963-0200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.00001 par value |
| Trading Symbol | WATT |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
