Summary of Significant Accounting Policies - NPC - Schedule of Allowance for Credit Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Charged to operating costs and expenses, net	$ 68	$ 43	$ 81
Write-offs, net	(72)	(45)	(50)
NPC
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	20	18	19
Charged to operating costs and expenses, net	18	14	13
Write-offs, net	(18)	(12)	(14)
Ending balance	$ 20	$ 20	$ 18