v3.20.1

Recently Adopted and Recently Issued Accounting Guidance | 3 Months Ended
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Mar. 31, 2020
Accounting Policies [Abstract] |
Recently Adopted and Recently Issued Accounting Guidance | Recently Adopted and Recently Issued Accounting Guidance​ Adopted On January 1, 2020, Arconic Corporation adopted changes issued by the Financial Accounting Standards Board (FASB) to credit losses. This guidance added a new impairment model (known as the current expected credit loss (CECL) model), which is based on expected losses rather than incurred losses. Under this model, an entity is required to recognize an allowance equivalent to its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. This model does not have a minimum threshold for recognition of impairment losses and requires the measurement of expected credit losses on assets that have a low risk of loss. The adoption of this guidance did not have a material impact on the Combined Financial Statements. This guidance will need to be considered in future assessments of credit losses. Issued In March 2020, the FASB issued amendments that provide optional guidance to ease the potential burden of reference rate reform on financial reporting. Under the amendments, expedients and exceptions are provided for applying GAAP to contracts, hedging relationships, and other transactions affected by the reform, if certain criteria are met, and apply only to those transactions which reference LIBOR or another reference rate that is expected to be discontinued. These amendments are effective immediately and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. Management is currently evaluating the potential impact of these changes on the Combined Financial Statements.

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- Definition The entire disclosure for all significant accounting policies of the reporting entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -URI http://asc.fasb.org/topic&trid=2122369 + Details
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