Long-term Debt - SPPC (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Par value	$ 52,313
Subsidiary debt, current	2,740	$ 3,201
Subsidiary debt, noncurrent	36,231	35,238
Maturity Schedule
2026	1,450
2029 and thereafter	43,313
Total	52,313
Subsidiary debt
Debt Instrument [Line Items]
Par value	39,012
Subsidiary debt	38,971	37,539
Subsidiary debt, current	2,740	2,301
Subsidiary debt, noncurrent	36,231	35,238
Maturity Schedule
Total	39,012
Subsidiary debt	38,971	37,539
SPPC
Debt Instrument [Line Items]
Par value	1,302
Subsidiary debt	1,293	1,148
Subsidiary debt, current	0	250
Subsidiary debt, noncurrent	1,293	898
Maturity Schedule
Total	1,302
Subsidiary debt	1,293	1,148
SPPC | Subsidiary debt
Debt Instrument [Line Items]
Par value	1,302
Subsidiary debt	1,293
Maturity Schedule
2026	400
2029 and thereafter	902
Total	1,302
Unamortized discount and debt issuance costs	(9)
Subsidiary debt	1,293
NV Energy | Subsidiary debt
Debt Instrument [Line Items]
Par value	4,736
Subsidiary debt	4,695	4,354
Maturity Schedule
2026	400
2029 and thereafter	4,336
Total	4,736
Subsidiary debt	4,695	4,354
NV Energy | SPPC | 3.375% Series T, due 2023
Debt Instrument [Line Items]
Par value	0
Maturity Schedule
Total	0
NV Energy | SPPC | 2.600% Series U, due 2026
Debt Instrument [Line Items]
Par value	400
Maturity Schedule
Total	400
NV Energy | SPPC | 6.750% Series P, due 2037
Debt Instrument [Line Items]
Par value	252
Maturity Schedule
Total	252
NV Energy | SPPC | 4.710% Series W, due 2052
Debt Instrument [Line Items]
Par value	250
Maturity Schedule
Total	250
NV Energy | SPPC | 5.900% Series 2023A, due 2054
Debt Instrument [Line Items]
Par value	400
Maturity Schedule
Total	$ 400
NV Energy | SPPC | Subsidiary debt | 3.375% Series T, due 2023
Debt Instrument [Line Items]
Stated rate	3.375%
Subsidiary debt	$ 0	249
Maturity Schedule
Subsidiary debt	$ 0	249
NV Energy | SPPC | Subsidiary debt | 2.600% Series U, due 2026
Debt Instrument [Line Items]
Stated rate	2.60%
Subsidiary debt	$ 398	397
Maturity Schedule
Subsidiary debt	$ 398	397
NV Energy | SPPC | Subsidiary debt | 6.750% Series P, due 2037
Debt Instrument [Line Items]
Stated rate	6.75%
Subsidiary debt	$ 254	254
Maturity Schedule
Subsidiary debt	$ 254	254
NV Energy | SPPC | Subsidiary debt | 4.710% Series W, due 2052
Debt Instrument [Line Items]
Stated rate	4.71%
Subsidiary debt	$ 248	248
Maturity Schedule
Subsidiary debt	$ 248	248
NV Energy | SPPC | Subsidiary debt | 5.900% Series 2023A, due 2054
Debt Instrument [Line Items]
Stated rate	5.90%
Subsidiary debt	$ 393	0
Maturity Schedule
Subsidiary debt	$ 393	$ 0