| Document and Entity Information | Sep. 18, 2019 |
| Cover [Abstract] | |
| Entity Registrant Name | ETSY INC |
| Document Period End Date | Sep. 18, 2019 |
| Amendment Flag | false |
| Entity Central Index Key | 0001370637 |
| Document Type | 8-K |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-36911 |
| Entity Tax Identification Number | 20-4898921 |
| Entity Address, Address Line One | 117 Adams Street |
| Entity Address, City or Town | Brooklyn |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 11201 |
| City Area Code | (718) |
| Local Phone Number | 880-3660 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.001 par value per share |
| Trading Symbol | ETSY |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
