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v3.25.3

Summary of Significant Accounting Policies - Additional Information (Details) | 9 Months Ended
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Sep. 28, 2025
Accounting Policies [Abstract] |
Length of fiscal quarters, weeks | 91 days

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- Definition Length of fiscal quarters, weeks + References No definition available. + Details
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Namespace Prefix: | gd_
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Balance Type: | na
Period Type: | duration

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- References No definition available. + Details
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