Divestitures	6 Months Ended
Jun. 30, 2020
Business Combinations [Abstract]
Divestitures	C. Divestitures – During the first quarter of 2020, the Company sold Elemental Environmental Solutions LLC (EES), a wholly-owned Alcoa subsidiary that operated the waste processing facility in Gum Springs, Arkansas, to a global environmental firm in a transaction valued at $250. At the close of the transaction the Company recorded a gain of $180 (pre- and after-tax; see Note Q) and received $200 with another $50 held in escrow to be paid to Alcoa if certain post-closing conditions are satisfied, which would result in additional gain being recorded. During the second quarter of 2020, an additional $1 gain was recorded as a result of certain post-closing adjustments based on the terms of the agreement. Further post-closing adjustments may occur related to this transaction and are not expected to be significant.

The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=2122178

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-URI http://asc.fasb.org/topic&trid=2303972

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