Interim Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Non-controlling Interests [Member]
Total stockholders' equity, beginning balance at Dec. 31, 2017	$ 865	$ 2	$ (116)	$ 837	$ 579	$ (442)	$ 5
Shares, beginning balance at Dec. 31, 2017		185,343,034	2,386,406
Common stock issued - compensation plans (in shares)		787,451
Exercise of stock options, net	15			15
Exercise of stock options, net (in shares)		1,018,962
Purchases of treasury stock, at cost	(520)		$ (520)
Purchases of treasury stock at cost (in shares)			10,926,065
Shares issued under employee stock purchase plan (in shares)			(12,411)
Stock-based compensation expense	20			20
Cancellation of unissued stock awards withheld to cover taxes	(16)			(16)
Net income	854				853		1
Dividends	(74)				(74)
Other comprehensive income (loss)	2					2
Total stockholders' equity, ending balance at Sep. 30, 2018	1,146	$ 2	$ (636)	856	1,358	(440)	6
Shares, ending balance at Sep. 30, 2018		187,149,447	13,300,060
Total stockholders' equity, beginning balance at Jun. 30, 2018	1,025	$ 2	$ (500)	859	1,127	(469)	6
Shares, beginning balance at Jun. 30, 2018		186,594,368	10,073,236
Common stock issued - compensation plans (in shares)		431,744
Exercise of stock options, net	2			2
Exercise of stock options, net (in shares)		123,335
Purchases of treasury stock, at cost	(136)		$ (136)
Purchases of treasury stock at cost (in shares)			3,226,824
Stock-based compensation expense	5			5
Cancellation of unissued stock awards withheld to cover taxes	(10)			(10)
Net income	275				275
Dividends	(44)				(44)
Other comprehensive income (loss)	29					29
Total stockholders' equity, ending balance at Sep. 30, 2018	1,146	$ 2	$ (636)	856	1,358	(440)	6
Shares, ending balance at Sep. 30, 2018		187,149,447	13,300,060
Total stockholders' equity, beginning balance at Dec. 31, 2018	1,020	$ 2	$ (750)	860	1,466	(564)	6
Shares, beginning balance at Dec. 31, 2018		187,204,567	16,424,093
Common stock issued - compensation plans				1	(1)
Common stock issued - compensation plans (in shares)		1,098,346
Exercise of stock options, net	8			8
Exercise of stock options, net (in shares)		508,773
Purchases of treasury stock, at cost	(322)		$ (322)
Purchases of treasury stock at cost (in shares)			8,895,142
Stock-based compensation expense	18			18
Cancellation of unissued stock awards withheld to cover taxes	(30)			(30)
Net income	265				265
Dividends	(124)				(124)
Other comprehensive income (loss)	8					8
Total stockholders' equity, ending balance at Sep. 30, 2019	843	$ 2	$ (1,072)	857	1,606	(556)	6
Shares, ending balance at Sep. 30, 2019		188,811,686	25,319,235
Total stockholders' equity, beginning balance at Jun. 30, 2019	829	$ 2	$ (1,072)	853	1,571	(531)	6
Shares, beginning balance at Jun. 30, 2019		188,801,201	25,319,235
Common stock issued - compensation plans (in shares)		6,807
Exercise of stock options, net (in shares)		3,678
Stock-based compensation expense	4			4
Net income	76				76
Dividends	(41)				(41)
Other comprehensive income (loss)	(25)					(25)
Total stockholders' equity, ending balance at Sep. 30, 2019	$ 843	$ 2	$ (1,072)	$ 857	$ 1,606	$ (556)	$ 6
Shares, ending balance at Sep. 30, 2019		188,811,686	25,319,235