Summary of Accounting Policies - Summary of Effect of Adopting New Accounting Standards on Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Item Effected [Line Items]
Decrease (increase) in receivables	$ (81)	$ (325)	$ (203)
Net cash provided by operating activities	517	374	415
Proceeds from deferred purchase price of factored receivables	112	110	113
Net cash used by investing activities	(300)	(229)	(192)
Increase(Decrease) in cash, cash equivalents and restricted cash	(31)	61	3
Cash, cash equivalents and restricted cash, January 1	349	288	285
Cash, cash equivalents and restricted cash, December 31	318	349	288
Previously Reported
Item Effected [Line Items]
Decrease (increase) in receivables	31	(215)	(90)
Net cash provided by operating activities	629	484	528
Change in restricted cash	(1)	(1)	2
Net cash used by investing activities	(413)	(340)	(303)
Increase(Decrease) in cash, cash equivalents and restricted cash	(32)	60	5
Cash, cash equivalents and restricted cash, January 1	347	287	282
Cash, cash equivalents and restricted cash, December 31	315	347	287
Effect of Accounting Change \| ASU 2016-18
Item Effected [Line Items]
Change in restricted cash	1	1	(2)
Net cash used by investing activities	1	1	(2)
Increase(Decrease) in cash, cash equivalents and restricted cash	1	1	(2)
Cash, cash equivalents and restricted cash, January 1	2	1	3
Cash, cash equivalents and restricted cash, December 31	3	2	1
Effect of Accounting Change \| ASU 2016-15
Item Effected [Line Items]
Decrease (increase) in receivables	(112)	(110)	(113)
Net cash provided by operating activities	(112)	(110)	(113)
Proceeds from deferred purchase price of factored receivables	112	110	113
Net cash used by investing activities	$ 112	$ 110	$ 113

Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

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The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The cash inflow associated with the proceeds from sale and collection of receivables during the period.

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