Leases - SPPC - Schedule of Operating and Finance Lease (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Right-of-use assets:
Operating leases	$ 545	$ 524
Finance lease right of use assets, net	418	448
Total right-of-use assets	$ 963	$ 972
Operating lease right-of-use asset, statement of financial position	Other assets	Other assets
Finance lease right-of-use asset, statement of financial position	Other assets	Other assets
Lease liabilities:
Operating leases	$ 605	$ 577
Finance leases	432	463
Total lease liabilities	$ 1,037	$ 1,040
Operating lease liability, statement of financial position	Other current liabilities, Other long-term liabilities	Other current liabilities, Other long-term liabilities
Finance lease liability, statement of financial position	Other current liabilities, Other long-term liabilities	Other current liabilities, Other long-term liabilities
SPPC
Right-of-use assets:
Operating leases	$ 16	$ 15
Finance lease right of use assets, net	105	111
Total right-of-use assets	$ 121	$ 126
Operating lease right-of-use asset, statement of financial position	Other assets	Other assets
Finance lease right-of-use asset, statement of financial position	Other assets	Other assets
Lease liabilities:
Operating leases	$ 15	$ 15
Finance leases	108	115
Total lease liabilities	$ 123	$ 130
Operating lease liability, statement of financial position	Other current liabilities, Other long-term liabilities	Other current liabilities, Other long-term liabilities
Finance lease liability, statement of financial position	Other current liabilities, Other long-term liabilities	Other current liabilities, Other long-term liabilities