CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities
Net loss	$ (497)	$ (206)	$ (888)	$ (377)
Adjustments to reconcile to net cash provided by operating activities:
Contract intangible asset amortization			101	92
Depreciation and amortization	196	219	402	436
Share-based compensation expense			15	19
Loss on impairment	429	1	597	1
Loss on impairment of investment in unconsolidated affiliate			59
Loss on disposal of assets, net	(1)	10		3
Loss on retirement of debt	(4)	9	53	27
Deferred income tax expense			30	109
Other, net			32	11
Changes in deferred revenues, net			(10)	4
Changes in deferred costs, net			(4)	(6)
Changes in other operating assets and liabilities, net			(348)	(217)
Net cash provided by operating activities			39	102
Cash flows from investing activities
Capital expenditures			(153)	(138)
Proceeds from disposal of assets, net			3	40
Investments in unconsolidated affiliates			(6)	(62)
Proceeds from maturities of unrestricted and restricted investments				123
Other, net				3
Net cash used in investing activities			(156)	(34)
Cash flows from financing activities
Proceeds from issuance of debt, net of discounts and issue costs			743	1,056
Repayments of debt			(1,009)	(834)
Other, net			(18)	(26)
Net cash provided by (used in) financing activities			(284)	196
Net increase (decrease) in unrestricted and restricted cash and cash equivalents			(401)	264
Unrestricted and restricted cash and cash equivalents, beginning of period			2,349	2,589
Unrestricted and restricted cash and cash equivalents, end of period	$ 1,948	$ 2,853	$ 1,948	$ 2,853