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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of the effect of a change in accounting principle on net income.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Other Comprehensive (Loss) Income and Shareholders' Equity - Changes in Shareholders' Equity (Deficit) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017	Jan. 01, 2016
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	$ 3,731
Balance at beginning of period (in shares)	359.1
Balance at beginning of period (as adjusted)	$ 3,566			$ 3,582
Net income	398	$ 371
Other comprehensive income	162	185
Dividends ($0.33 per share)	(118)
Share-based compensation plans	$ (48)
Share-based compensation plans (in shares)	1.3
Purchase of treasury stock	$ (782)
Purchase of treasury stock (in shares)	(5.6)
Balance at end of period	$ 3,566
Balance at end of period (in shares)	354.8
Cash dividends (in USD per share)	$ 0.33
Class A Common Stock
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	$ 5
Balance at beginning of period (as adjusted)				5
Balance at end of period	5
Additional Paid-in- Capital
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	5,770
Balance at beginning of period (as adjusted)				5,770
Share-based compensation plans	(85)
Balance at end of period	5,685
Retained Earnings
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	7,391
Balance at beginning of period (as adjusted)				7,242
Net income	398
Dividends ($0.33 per share)	(118)
Balance at end of period	7,898
Treasury Stock, at Cost
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	(9,418)
Balance at beginning of period (as adjusted)				(9,418)
Share-based compensation plans	37
Purchase of treasury stock	(782)
Balance at end of period	(10,163)
Accumulated Other Comprehensive Loss
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Balance at beginning of period	(17)	(497)
Balance at beginning of period (as adjusted)				(17)
Other comprehensive income	162
Balance at end of period	141	$ (312)
Adoption of ASU 2014-09
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09				(149)
Adoption of ASU 2014-09 \| Retained Earnings
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09				(149)	$ 264
Adoption of ASU 2014-09 \| Accumulated Other Comprehensive Loss
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09				0
Adoption of ASU 2016-01
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU	0
Adoption of ASU 2016-01 \| Retained Earnings
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09			$ 4
Adoption of ASU	4
Adoption of ASU 2016-01 \| Accumulated Other Comprehensive Loss
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09				$ (4)
Adoption of ASU	(4)
Adoption of ASU 2016-16
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU	372
Adoption of ASU 2016-16 \| Retained Earnings
(Increase) Decrease in Shareholders' Deficit [Roll Forward]
Adoption of ASU 2014-09			$ 372
Adoption of ASU	$ 372