Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net (loss) income	$ (20)	$ 30	$ (67)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	150	130	138
Stock-based compensation expense	83	65	68
Deferred income taxes	(3)	(18)	(34)
Changes in assets and liabilities, net of acquisitions:
Receivables	190	(34)	(6)
Inventories	(3)	2	3
Account payables and accrued expenses	(153)	108	12
Deferred revenue	(62)	115	115
Other assets and liabilities	(34)	(34)	95
Net cash provided by operating activities	148	364	324
Investing activities
Expenditures for property and equipment	(54)	(153)	(78)
Additions to capitalized software	(5)	(7)	(9)
Business acquisitions and other investing activities, net	0	(3)	(21)
Net cash used in investing activities	(59)	(163)	(108)
Financing activities
Repayments of long-term borrowings	(19)	(40)	(30)
Proceeds from credit facility borrowings	0	0	420
Repayments of credit-facility borrowings	0	(240)	(180)
Repurchases of common stock	(300)	(300)	(351)
Payments of finance leases	(33)	(5)	0
Other financing activities, net	44	31	32
Net cash used in financing activities	(308)	(554)	(109)
Effect of exchange rate changes on cash and cash equivalents	(1)	(20)	8
(Decrease) increase in cash, cash equivalents and restricted cash	(220)	(373)	115
Total cash, cash equivalents and restricted cash	716	1,089	974
Cash, cash equivalents and restricted cash at end of year	496	716	1,089
Reconciliation of cash, cash equivalents and restricted cash to the Consolidated Balance Sheets
Total cash, cash equivalents and restricted cash	716	1,089	1,089
Non-cash investing and financing activities:
Assets acquired by finance lease	115	52	0
Assets acquired by operating lease	6	0	0
Cash paid during the year for:
Income taxes	33	33	25
Interest	$ 26	$ 23	$ 14