CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
OPERATING REVENUE	$ 23,443	$ 17,656	$ 17,470
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	10,862	8,203	7,774
Selling, general and administrative	4,165	3,508	3,447
Depreciation and amortization	5,120	3,936	3,916
Goodwill impairment	2,726	0	0
Total operating expenses	22,873	15,647	15,137
OPERATING INCOME	570	2,009	2,333
OTHER (EXPENSE) INCOME
Interest expense	(2,177)	(1,481)	(1,318)
Other income, net	44	12	5
Total other expense, net	(2,133)	(1,469)	(1,313)
INCOME (LOSS) BEFORE INCOME TAX EXPENSE	(1,563)	540	1,020
Income tax expense (benefit)	170	(849)	394
NET (LOSS) INCOME	$ (1,733)	$ 1,389	$ 626
BASIC AND DILUTED (LOSS) EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ (1.63)	$ 2.21	$ 1.16
DILUTED (in dollars per share)	$ (1.63)	$ 2.21	$ 1.16
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	1,065,866	627,808	539,549
DILUTED (in shares)	1,065,866	628,693	540,679