Consolidated Balance Sheet (unaudited) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents (M)	$ 1,396	$ 944
Receivables from customers (I)	939	656
Other receivables	135	152
Inventories (J)	1,975	2,158
Fair value of derivative instruments (M)	38	29
Prepaid expenses and other current assets	420	466
Total current assets	4,903	4,405
Properties, plants, and equipment	19,999	20,381
Less: accumulated depreciation, depletion, and amortization	13,496	13,596
Properties, plants, and equipment, net	6,503	6,785
Investments (H)	989	979
Deferred income taxes	311	333
Fair value of derivative instruments (M)	0	3
Other noncurrent assets	1,601	1,650
Total assets	14,307	14,155
Current liabilities:
Accounts payable, trade	1,619	1,714
Accrued compensation and retirement costs	358	357
Taxes, including income taxes	119	88
Fair value of derivative instruments (M)	251	214
Other current liabilities	740	578
Long-term debt due within one year (K & M)	79	79
Total current liabilities	3,166	3,030
Long-term debt, less amount due within one year (K & M)	2,469	1,732
Accrued pension benefits (L)	264	278
Accrued other postretirement benefits (L)	427	443
Asset retirement obligations	699	772
Environmental remediation (O)	191	202
Fair value of derivative instruments (M)	951	1,092
Noncurrent income taxes	133	193
Other noncurrent liabilities and deferred credits	591	568
Total liabilities	8,891	8,310
CONTINGENCIES AND COMMITMENTS (O)
Alcoa Corporation shareholders’ equity:
Common stock	2	2
Additional capital	9,196	9,187
Accumulated deficit	(1,562)	(1,293)
Accumulated other comprehensive loss (G)	(3,737)	(3,645)
Total Alcoa Corporation shareholders’ equity	3,899	4,251
Noncontrolling interest	1,517	1,594
Total equity	5,416	5,845	$ 6,589
Total liabilities and equity	$ 14,307	$ 14,155