Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Weighted-Average Useful Lives of Structures and Machinery and Equipment

The following table details the weighted average useful lives of structures and machinery and equipment by type of operation (numbers in years):

	Structures		Machinery and equipment
Alumina		29		27
Aluminum smelting and casting		37		22
Energy generation		33		25

Weighted-Average Useful Lives of Software and Other Intangible Assets

The following table details the weighted average useful lives of software and other intangible assets by type of operation (numbers in years):

	Software		Other intangible assets
Alumina		6		25
Aluminum smelting and casting		3		40
Energy generation		3		29