Employee Benefits - Schedule of Fair Value of Defined Benefit Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	$ 1,473	$ 1,464
Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	1,028	1,171
Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	3	11
Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	991	1,126
Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	34	34
Common collective trust funds measured at net asset value as a practical expedient
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	445	293
Cash and short-term investments | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	3	5
Cash and short-term investments | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	3	5
Cash and short-term investments | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
Cash and short-term investments | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
U.S. indexes | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		6
U.S. indexes | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		6
U.S. indexes | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		0
U.S. indexes | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		0
Long duration strategy | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	991	1,007
Long duration strategy | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
Long duration strategy | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	991	1,007
Long duration strategy | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
Intermediate duration securities | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		38
Intermediate duration securities | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		0
Intermediate duration securities | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		38
Intermediate duration securities | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		0
Real Estate: U.K. | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	34	34
Real Estate: U.K. | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
Real Estate: U.K. | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	0	0
Real Estate: U.K. | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets	$ 34	34
Infrastructure: U.K. | Total
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		81
Infrastructure: U.K. | Level 1
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		0
Infrastructure: U.K. | Level 2
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		81
Infrastructure: U.K. | Level 3
Fair value of defined benefit plans assets by asset class
Fair value of plan assets		$ 0