CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
OPERATING REVENUE	$ 3,738	$ 4,676
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	1,817	1,985
Selling, general and administrative	721	800
Loss on disposal group held for sale	77	0
Depreciation and amortization	733	808
Total operating expenses	3,348	3,593
OPERATING INCOME	390	1,083
OTHER INCOME (EXPENSE)
Interest expense	(279)	(352)
Net gain on early retirement of debt (Note 6)	609	0
Other (expense) income, net	(40)	70
Total other income (expense), net	290	(282)
INCOME BEFORE INCOME TAXES	680	801
Income tax expense	169	202
NET INCOME	$ 511	$ 599
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.52	$ 0.59
DILUTED (in dollars per share)	$ 0.52	$ 0.59
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	981,555	1,008,430
DILUTED (in shares)	982,283	1,015,215