CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
OPERATING REVENUES	$ 4,401	$ 4,451
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	1,900	1,911
Selling, general and administrative	831	851
Depreciation and amortization	976	1,040
Total operating expenses	3,707	3,802
OPERATING INCOME	694	649
OTHER (EXPENSE) INCOME
Interest expense	(331)	(328)
Other income, net	17	2
Total other expense, net	(314)	(326)
INCOME BEFORE INCOME TAX EXPENSE	380	323
Income tax expense	144	131
Net income	$ 236	$ 192
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.44	$ 0.34
DILUTED (in dollars per share)	0.44	0.34
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.54	$ 0.54
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	538,799	561,969
DILUTED (in shares)	540,187	563,505