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v3.23.1

Exit Activity Costs and Asset Impairments (Narrative) (Details) | 3 Months Ended
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Mar. 31, 2022 facility
Restructuring and Related Activities [Abstract] |
Number of facilities closed | 1

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- Definition Restructuring and Related Cost, Number of Facilities to be Closed + References No definition available. + Details
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Namespace Prefix: | rock_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- References No definition available. + Details
Name: | us-gaap_RestructuringAndRelatedActivitiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration