Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]
Minimum pension and post retirement benefit plan adjustments, net of taxes	$ (36)	$ (449)	$ (43)

Other Comprehensive Income Minimum Pension Liability Net Adjustment Tax 1

No definition available.

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Namespace Prefix:	rock_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration