Debt, Credit Facilities and Financings - Schedule of Line of Credit Facilities (Details) $ in Millions	Mar. 31, 2025 USD ($)
Debt Instrument [Line Items]
Facility Limit	$ 8,723
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	3,533
Letters of Credit Outstanding	1,223
Available Capacity	3,342
Line of Credit
Debt Instrument [Line Items]
Facility Limit	5,909
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	2,469
Letters of Credit Outstanding	1,223
Available Capacity	2,217
Vistra Operations debt
Debt Instrument [Line Items]
Facility Limit	7,659
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	2,469
Letters of Credit Outstanding	1,223
Available Capacity	3,342
Project-level debt
Debt Instrument [Line Items]
Facility Limit	1,064
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	1,064
Letters of Credit Outstanding	0
Available Capacity	0
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	0
Letters of Credit Outstanding	1,223
Available Capacity	2,217
Term Loan B-3 Facility | Line of Credit
Debt Instrument [Line Items]
Letters of Credit Outstanding	0
Available Capacity	0
Vistra Operations Commodity-Linked Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	0
Letters of Credit Outstanding	0
Available Capacity	1,125
BCOP Credit Facility, Tax Credit Bridge Loan due November 1, 2025 / December 3, 2026
Debt Instrument [Line Items]
Facility Limit	367
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	367
Letters of Credit Outstanding	0
Available Capacity	0
BCOP Credit Facility, Tax Credit Bridge Loan due November 1, 2025 / December 3, 2026 | Bridge Loan | Oak Hill
Debt Instrument [Line Items]
Facility Limit	106
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	106
Letters of Credit Outstanding	0
Available Capacity	0
BCOP Credit Facility, Tax Credit Bridge Loan due November 1, 2025 / December 3, 2026 | Bridge Loan | Pulaski
Debt Instrument [Line Items]
Facility Limit	261
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	261
Letters of Credit Outstanding	0
Available Capacity	0
Vistra Zero Term Loan B Facility | Revolving Credit Facility
Debt Instrument [Line Items]
Facility Limit	697
Cash Borrowings (Long-Term Debt, Including Amounts Due Currently)	697
Letters of Credit Outstanding	0
Available Capacity	$ 0