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v3.19.3.a.u2

Summary of Significant Accounting Policies - Weighted-Average Useful Lives of Software and Other Intangible Assets (Details) | 12 Months Ended
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Dec. 31, 2019
Software | Engineered Products and Forgings |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average useful lives of other intangible assets | 5 years
Software | Global Rolled Products |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average useful lives of other intangible assets | 5 years
Other intangible assets | Engineered Products and Forgings |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average useful lives of other intangible assets | 32 years
Other intangible assets | Global Rolled Products |
Finite-Lived Intangible Assets [Line Items] |
Weighted-average useful lives of other intangible assets | 13 years

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- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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Balance Type: | na
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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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- Details
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- Details
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- Details
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- Details
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