CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Consolidated net income	$ 562	$ 406
Adjustments to reconcile consolidated net income to net cash flows from operating activities:
Depreciation and amortization	5,302	5,145
Stock compensation expense	142	134
Accelerated vesting of equity awards	5	37
Noncash interest income, net	(177)	(196)
Loss on extinguishment of debt	0	35
Loss on financial instruments, net	12	32
Deferred income taxes	57	42
Other, net	36	(18)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	16	61
Prepaid expenses and other assets	(91)	(23)
Accounts payable, accrued liabilities and other	(69)	133
Net cash flows from operating activities	5,795	5,788
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(4,574)	(3,703)
Change in accrued expenses related to capital expenditures	(466)	197
Other, net	(67)	(49)
Net cash flows from investing activities	(5,107)	(3,555)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings of long-term debt	5,628	7,146
Repayments of long-term debt	(3,500)	(5,529)
Payments for debt issuance costs	(17)	(42)
Purchase of treasury stock	(2,281)	(4,223)
Proceeds from exercise of stock options	43	86
Purchase of noncontrolling interest	(328)	(429)
Distributions to noncontrolling interest	(76)	(75)
Other, net	(5)	(8)
Net cash flows from financing activities	(536)	(3,074)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	152	(841)
CASH AND CASH EQUIVALENTS, beginning of period	621	1,535
CASH AND CASH EQUIVALENTS, end of period	773	694
CASH PAID FOR INTEREST	1,889	1,653
CASH PAID FOR TAXES	$ 22	$ 33