| Cover | Dec. 10, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Dec. 10, 2024 |
| Entity Registrant Name | Talen Energy Corporation |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-37388 |
| Entity Tax Identification Number | 47-1197305 |
| Entity Address, Address Line One | 2929 Allen Pkwy, Suite 2200 |
| Entity Address, City or Town | Houston |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77019 |
| City Area Code | 888 |
| Local Phone Number | 211-6011 |
| 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 $0.001 per share |
| Trading Symbol | TLN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001622536 |
