CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common shares:	Other capital:	Retained earnings (accumulated deficit):	Accumulated other comprehensive loss:
Balance at beginning of year at Dec. 31, 2016		$ 936	$ 8,282	$ 1,421	$ (1,459)
Issued for exercise of stock options and vested restricted stock units		8	128
Repurchases of common shares (Note 15)		0	0
Share-based compensation			35
Other transactions, net			(6)
Net earnings (loss)	$ 582			582
Dividends on common shares				(944)
Adjustments related to new accounting pronouncements (Note 1)				19
Other comprehensive income					(103)
Adjustments related to new accounting pronouncements and other (Note 15)					0
Balance at end of year at Dec. 31, 2017	$ 8,899	944	8,439	1,078	(1,562)
Dividends paid per common share	$ 1.25
Issued for exercise of stock options and vested restricted stock units		4	49
Repurchases of common shares (Note 15)		(15)	(351)
Share-based compensation			42
Other transactions, net			(7)
Net earnings (loss)	$ 748			748
Dividends on common shares				(995)
Adjustments related to new accounting pronouncements (Note 1)				262
Other comprehensive income					672
Adjustments related to new accounting pronouncements and other (Note 15)					(262)
Balance at end of year at Dec. 31, 2018	$ 9,046	933	8,172	1,093	(1,152)
Dividends paid per common share	$ 1.32
Issued for exercise of stock options and vested restricted stock units		2	12
Repurchases of common shares (Note 15)		(3)	(57)
Share-based compensation			30
Other transactions, net			(5)
Net earnings (loss)	$ (76)			(76)
Dividends on common shares				(1,013)
Adjustments related to new accounting pronouncements (Note 1)				(7)
Other comprehensive income					248
Adjustments related to new accounting pronouncements and other (Note 15)					0
Balance at end of year at Dec. 31, 2019	$ 8,177	$ 932	$ 8,152	$ (3)	$ (904)
Dividends paid per common share	$ 1.36