Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating activities
Net (loss) income	$ (11)	$ (3)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	77	64
Stock-based compensation expense	37	35
Deferred income taxes	0	(6)
Changes in assets and liabilities:
Receivables	211	185
Inventories	(7)	2
Current payables and accrued expenses	(155)	(31)
Deferred revenue	(15)	90
Other assets and liabilities	(33)	(46)
Net cash provided by operating activities	104	290
Investing activities
Expenditures for property and equipment	(27)	(58)
Additions to capitalized software	(2)	(4)
Net cash used in investing activities	(29)	(62)
Financing activities
Repurchases of common stock	(175)	(157)
Repayments of long-term borrowings	(6)	(40)
Repayments of credit facility borrowings	0	(240)
Payments of finance leases	(9)	0
Other financing activities, net	36	18
Net cash used in financing activities	(154)	(419)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0	(15)
Decrease in cash, cash equivalents and restricted cash	(79)	(206)
Cash, cash equivalents and restricted cash at beginning of period	716	1,089
Cash, cash equivalents and restricted cash at end of period	637	883
Supplemental cash flow disclosure:
Assets acquired under operating lease	4	0
Assets acquired under finance lease	48	0
Total cash, cash equivalents and restricted cash	$ 637	$ 1,089