Employee Benefit Plans - SPPC (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 3
U.S. | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	7
SPPC | U.S. | Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	2
SPPC | U.S. | NV Energy | Other Current Liabilities | Other Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Other current liabilities	(1)	$ (1)
SPPC | U.S. | NV Energy | Other Noncurrent Liabilities | Other Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Other long-term liabilities	(5)	(5)
SPPC | U.S. | NV Energy | Other Noncurrent Liabilities | Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Other long-term liabilities	0	(2)
SPPC | Qualified Plan | U.S. | NV Energy | Other Assets | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Other non-current assets	$ 44	$ 43