Spinoff Transaction, Consideration Transferred, Equity Interests Issued and Issuable

No definition available.

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Namespace Prefix:	arnc_
Data Type:	xbrli:sharesItemType
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

+ Details

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Data Type:	dtr-types:perShareItemType
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Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Earnings Per Share - Narrative (Details) - $ / shares	Dec. 31, 2020	Apr. 01, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Separation transaction, shares issued to parent		109,021,376	109,021,376
Exercise Price Greater Than Average Market Price
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock options outstanding (in shares)	500,000
Weighted average exercise price of stock options outstanding (in dollars per share)	$ 33.32