CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ in Millions	Total controlling interest shareholders' equity	Shares	Additional paid-in capital	Treasury shares, at cost	Retained earnings	Accumulated other comprehensive loss	Noncontrolling interest	Total
Balance at Dec. 31, 2013	$ 16,717	$ 5,147	$ 6,784	$ (240)	$ 5,252	$ (226)	$ 2	$ 16,719
Balance (in shares) at Dec. 31, 2013		361
Increase (Decrease) in Shareholders' Equity
Share-based compensation	98		98					98
Issuance of shares under share-based compensation plans		$ 22	(21)
Issuance of shares under share-based compensation plans (in shares)		1
Reclassification of obligation for distribution of qualifying additional paid-in capital	(1,088)		(1,088)					(1,088)
Allocated capital for transactions with holders of noncontrolling interest	33		33				(33)
Net income (loss) attributable to controlling interest					(1,839)			(1,839)
Other comprehensive income (loss) attributable to controlling interest						(120)		(120)
Total comprehensive income attributable to noncontrolling interest							(70)
Total comprehensive income attributable to controlling interest	(1,959)							(1,959)
Total comprehensive income								(2,029)
Sale of noncontrolling interest, net of issue costs							417	417
Distributions to holders of noncontrolling interest							(5)	(5)
Other, net	(8)		(9)					(8)
Balance at Dec. 31, 2014	13,793	$ 5,169	5,797	(240)	3,413	(346)	311	14,104
Balance (in shares) at Dec. 31, 2014		362
Increase (Decrease) in Shareholders' Equity
Share-based compensation	64		64					64
Issuance of shares under share-based compensation plans		$ 24	(24)
Issuance of shares under share-based compensation plans (in shares)		2
Reclassification of obligation for distribution of qualifying additional paid-in capital	(109)		(109)					(109)
Allocated capital for transactions with holders of noncontrolling interest	9		9				(9)
Net income (loss) attributable to controlling interest					865			865
Other comprehensive income (loss) attributable to controlling interest						69		69
Total comprehensive income attributable to noncontrolling interest							38
Total comprehensive income attributable to controlling interest	934							934
Total comprehensive income								972
Acquisition of noncontrolling interest							(1)	(1)
Distributions to holders of noncontrolling interest							(29)	(29)
Other, net	(1)		(1)					(1)
Balance at Dec. 31, 2015	14,690	$ 5,193	5,736	(240)	4,278	(277)	310	15,000
Balance (in shares) at Dec. 31, 2015		364
Increase (Decrease) in Shareholders' Equity
Share-based compensation	42		42					42
Reduction of par value		$ (5,159)	5,159
Cancellation of shares held in treasury			(240)	$ 240
Issuance of shares for acquisition of noncontrolling interest, net of issue costs	315	$ 2	313					315
Issuance of shares for acquisition of noncontrolling interest (in shares)		24
Issuance of shares under share-based compensation plans (in shares)		1
Allocated capital for transactions with holders of noncontrolling interest	(18)		(18)				18
Net income (loss) attributable to controlling interest					778			778
Other comprehensive income (loss) attributable to controlling interest						(6)		(6)
Total comprehensive income attributable to noncontrolling interest							26
Total comprehensive income attributable to controlling interest	772							772
Total comprehensive income								798
Acquisition of noncontrolling interest							(321)	(321)
Distributions to holders of noncontrolling interest							(30)	(30)
Other, net	1		1					1
Balance at Dec. 31, 2016	$ 15,802	$ 36	$ 10,993		$ 5,056	$ (283)	$ 3	$ 15,805
Balance (in shares) at Dec. 31, 2016		389