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 period at Dec. 31, 2018		$ 933	$ 8,172	$ 1,093	$ (1,152)
Issued for exercise of stock options and vested restricted stock units		1	4
Repurchases of common shares (Note 4)		(3)	(57)
Shared-based compensation			16
Other transactions, net			(5)
Net earnings (loss)	$ (161)			(161)
Dividends on common shares				(507)
Adjustments related to accounting pronouncements and other				(7)
Other comprehensive income					397
Balance at end of period at Jun. 30, 2019	$ 8,724	931	8,130	418	(755)
Dividends paid per common share	$ 0.68
Balance at beginning of period at Mar. 31, 2019		931	8,121	543	(794)
Issued for exercise of stock options and vested restricted stock units		0	2
Repurchases of common shares (Note 4)		0	0
Shared-based compensation			7
Other transactions, net			0
Net earnings (loss)	$ 128			128
Dividends on common shares				(253)
Adjustments related to accounting pronouncements and other				0
Other comprehensive income					39
Balance at end of period at Jun. 30, 2019	$ 8,724	931	8,130	418	(755)
Dividends paid per common share	$ 0.34
Balance at beginning of period at Dec. 31, 2019	$ 8,177	932	8,152	(3)	(904)
Issued for exercise of stock options and vested restricted stock units		1	6
Repurchases of common shares (Note 4)		0	0
Shared-based compensation			15
Other transactions, net			(7)
Net earnings (loss)	222			222
Dividends on common shares				(256)
Adjustments related to accounting pronouncements and other				0
Other comprehensive income					44
Balance at end of period at Jun. 30, 2020	$ 8,202	933	8,166	(37)	(860)
Dividends paid per common share	$ 0.34
Balance at beginning of period at Mar. 31, 2020		933	8,159	(109)	(901)
Issued for exercise of stock options and vested restricted stock units		0	0
Repurchases of common shares (Note 4)		0	0
Shared-based compensation			8
Other transactions, net			(1)
Net earnings (loss)	$ 72			72
Dividends on common shares				0
Adjustments related to accounting pronouncements and other				0
Other comprehensive income					41
Balance at end of period at Jun. 30, 2020	$ 8,202	$ 933	$ 8,166	$ (37)	$ (860)
Dividends paid per common share	$ 0