Equity - Summary of Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017
Dividends declared per share (usd per share)	$ 0.24	$ 0.21
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 2,782	$ 2,519
Cumulative effect of change in accounting principle			$ (3)
Sale of business	(2)
Net income	79	79
Other comprehensive income (loss), net	20	20
Dividends declared	(44)	(38)
Stock incentive plan activity	(2)	5
Repurchase of common stock	(25)	(25)
Ending balance	2,808	2,557
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	2	2
Ending balance	2	2
Capital in Excess of Par Value
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,950	1,912
Stock incentive plan activity	12	13
Ending balance	1,962	1,925
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,639	1,227
Cumulative effect of change in accounting principle			14
Net income	79	79
Dividends declared	(44)	(38)
Ending balance	1,674	1,282
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(336)	(210)
Cumulative effect of change in accounting principle			$ (17)
Other comprehensive income (loss), net	20	20
Ending balance	(316)	(207)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(487)	(428)
Stock incentive plan activity	(14)	(8)
Repurchase of common stock	(25)	(25)
Ending balance	(526)	(461)
Non-Controlling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	14	16
Sale of business	(2)
Ending balance	$ 12	$ 16

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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