Statement of Combined Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net income	$ 16	$ 5	$ (359)	$ (45)
Other comprehensive income, net of tax
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	45	31	637	92
Foreign currency translation adjustments	(11)	37	(5)	42
Net change in unrecognized losses on cash flow hedges	(13)	12	(49)	5
Total Other comprehensive income, net of tax	21	80	583	139
Comprehensive income	37	85	224	94
Arconic Corporation
Net income	16	5	(359)	(45)
Other comprehensive income, net of tax
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	45	31	637	92
Foreign currency translation adjustments	(11)	37	(5)	42
Net change in unrecognized losses on cash flow hedges	(13)	12	(49)	5
Total Other comprehensive income, net of tax	21	80	583	139
Comprehensive income	37	85	224	94
Noncontrolling interest
Net income	0	0	0	0
Other comprehensive income, net of tax
Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits	0	0	0	0
Foreign currency translation adjustments	0	0	0	0
Net change in unrecognized losses on cash flow hedges	0	0	0	0
Total Other comprehensive income, net of tax	0	0	0	0
Comprehensive income	$ 0	$ 0	$ 0	$ 0