CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
OPERATING REVENUES	$ 4,209	$ 4,401
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	1,888	1,900
Selling, general and administrative	810	837
Depreciation and amortization	880	976
Total operating expenses	3,578	3,713
OPERATING INCOME	631	688
OTHER (EXPENSE) INCOME
Interest expense	(318)	(331)
Other (expense) income, net	(6)	23
Total other expense, net	(324)	(308)
INCOME BEFORE INCOME TAX EXPENSE	307	380
Income tax expense	144	144
NET INCOME	$ 163	$ 236
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (per share)	$ 0.30	$ 0.44
DILUTED (per share)	0.30	0.44
DIVIDENDS DECLARED PER COMMON SHARE	$ 0.54	$ 0.54
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	540,458	538,799
DILUTED (in shares)	541,522	540,187