| Document And Entity Information | Nov. 06, 2019 |
| Document Information [Line Items] | |
| Entity Registrant Name | CLEARWAY ENERGY, INC. |
| Document Type | 8-K |
| Document Period End Date | Nov. 6, 2019 |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-36002 |
| Entity Tax Identification Number | 46-1777204 |
| Entity Address, Address Line One | 300 Carnegie Center, Suite 300 |
| Entity Address, City or Town | Princeton |
| Entity Address, State or Province | NJ |
| Entity Address, Postal Zip Code | 08540 |
| City Area Code | 609 |
| Local Phone Number | 608-1525 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001567683 |
| ClassACommonStock Custom [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Class A Common Stock |
| Trading Symbol | CWEN.A |
| Security Exchange Name | NYSE |
| ClassCCommonStock Custom [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Class C Common Stock |
| Trading Symbol | CWEN |
| Security Exchange Name | NYSE |
