| Cover Page | Jan. 04, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jan. 4, 2022 |
| Entity Registrant Name | Sunrun Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-37511 |
| Entity Tax Identification Number | 26-2841711 |
| Entity Address, Address Line One | 225 Bush Street |
| Entity Address, Address Line Two | Suite 1400 |
| Entity Address, City or Town | San Francisco |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94104 |
| City Area Code | 415 |
| Local Phone Number | 580-6900 |
| 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 $0.0001 per share |
| Trading Symbol | RUN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001469367 |
| Amendment Flag | false |
