v3.20.1

Subsequent Events​	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events​ Management evaluated all activity of Arconic Corporation and concluded that no subsequent events have occurred that would require recognition in the Combined Financial Statements or disclosure in the Notes to the Combined Financial Statements, except as described below. On April 1, 2020, ParentCo completed its separation into two standalone, publicly-traded companies (see Note A). On April 2, 2020, Arconic Corporation borrowed $500 under its revolving credit facility (see Note L). On April 8, 2020, Arconic Corporation initiated a series of actions to mitigate the impacts of the COVID-19 pandemic on the Company (see Note A). On May 13, 2020, Arconic Corporation executed a refinancing of certain of its existing financing arrangements (see Note L).

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No definition available.

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- Definition

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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