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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2020
Accounting Policies [Abstract] |
Weighted-Average Useful Lives of Structures and Machinery and Equipment | The following table details the weighted-average useful lives of structures and machinery and equipment by reporting segment (numbers in years):
| Structures |  | Machinery and equipment
Engine Products | 30 |  | 16
Fastening Systems | 28 |  | 17
Engineered Structures | 28 |  | 18
Forged Wheels | 29 |  | 18
Weighted-Average Useful Lives of Software and Other Intangibles | The following table details the weighted-average useful lives of software and other intangible assets by reporting segment (numbers in years):
| Software |  | Other intangible assets
Engine Products | 7 |  | 33
Fastening Systems | 6 |  | 23
Engineered Structures | 4 |  | 10
Forged Wheels | 4 |  | 23

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