CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
OPERATING REVENUE	$ 4,390	$ 4,887	$ 13,678	$ 14,840
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	1,999	2,151	6,042	6,402
Selling, general and administrative	792	654	2,407	2,172
Gain on sale of business	(593)	0	(593)	0
Depreciation and amortization	808	951	2,443	3,142
Total operating expenses	3,006	3,756	10,299	11,716
OPERATING INCOME	1,384	1,131	3,379	3,124
OTHER (EXPENSE) INCOME
Interest expense	(363)	(377)	(1,052)	(1,150)
Other (expense) income, net	(84)	(38)	(136)	48
Total other expense, net	(447)	(415)	(1,188)	(1,102)
INCOME BEFORE INCOME TAXES	937	716	2,191	2,022
Income tax expense	359	172	670	497
NET INCOME	$ 578	$ 544	$ 1,521	$ 1,525
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.57	$ 0.51	$ 1.50	$ 1.42
DILUTED (in dollars per share)	$ 0.57	$ 0.51	$ 1.50	$ 1.41
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	1,013,124	1,062,084	1,011,498	1,077,106
DILUTED (in shares)	1,017,013	1,069,157	1,016,281	1,083,879