Segment and Geographic Information - Schedule of Geographic Distributions of Revenues, Equity in Earnings of Affiliates, Adjusted Segment EBITDA, Depreciation and Amortization (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Revenues	$ 17,492	$ 15,861	$ 34,831	$ 31,452
Equity in (earnings) losses of affiliates	0	7	2	25
Adjusted segment EBITDA	3,550	3,056	6,903	6,228
Depreciation and amortization	819	763	1,614	1,519
Interest expense	506	485	1,018	964
Losses (gains) on sales of facilities	(12)	(1)	(213)	14
Income before income taxes	2,237	1,809	4,484	3,731
National Group [Member]
Segment Reporting Information [Line Items]
Revenues	4,817	4,372	9,612	8,988
Equity in (earnings) losses of affiliates	3	(1)	2	(2)
Adjusted segment EBITDA	1,104	878	2,172	2,027
Depreciation and amortization	211	208	423	415
Atlantic Group [Member]
Segment Reporting Information [Line Items]
Revenues	5,719	5,038	11,396	10,147
Equity in (earnings) losses of affiliates	(1)	(1)	(2)	(2)
Adjusted segment EBITDA	1,314	975	2,603	2,061
Depreciation and amortization	261	247	519	486
American Group [Member]
Segment Reporting Information [Line Items]
Revenues	5,978	5,536	11,892	10,735
Equity in (earnings) losses of affiliates	(18)	(10)	(31)	(22)
Adjusted segment EBITDA	1,420	1,319	2,740	2,452
Depreciation and amortization	267	238	522	475
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues	978	915	1,931	1,582
Equity in (earnings) losses of affiliates	16	19	33	51
Adjusted segment EBITDA	(288)	(116)	(612)	(312)
Depreciation and amortization	$ 80	$ 70	$ 150	$ 143