Cash and Cash Equivalents and Restricted Cash and Cash Equivalents - NPC (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Condensed Cash Flow Statements, Captions [Line Items]
Cash and cash equivalents	$ 2,229	$ 1,591
Restricted cash and cash equivalents, current	158	173
Total cash and cash equivalents and restricted cash and cash equivalents	2,440	1,817	$ 2,301	$ 1,244
NPC
Condensed Cash Flow Statements, Captions [Line Items]
Cash and cash equivalents	47	43
Restricted cash and cash equivalents, current	15	17
Total cash and cash equivalents and restricted cash and cash equivalents	$ 62	$ 60	$ 55	$ 45