XML 53 R41.htm IDEA: XBRL DOCUMENT v3.25.2

Acquisition (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands		6 Months Ended
	Feb. 11, 2025	Jun. 30, 2025
Lane Supply
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 67,100
Lane Supply | Trademarks
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 6,800
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	20 years
Lane Supply | Customer relationships
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 55,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	15 years
Lane Supply | Backlog
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 5,300
Two Metal Roofing Businesses
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 22,340
Two Metal Roofing Businesses | Trademarks
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 3,870
Two Metal Roofing Businesses | Trademarks | Minimum
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years
Two Metal Roofing Businesses | Trademarks | Maximum
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		11 years
Two Metal Roofing Businesses | Customer relationships
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 18,470
Two Metal Roofing Businesses | Customer relationships | Minimum
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		9 years
Two Metal Roofing Businesses | Customer relationships | Maximum
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years

X

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481283/985-20-50-2

+ Details

Name:	us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479907/805-20-50-5

+ Details

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-1

+ Details

Name:	us-gaap_FinitelivedIntangibleAssetsAcquired1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=rock_LaneSupplyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_TrademarksMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_CustomerRelationshipsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=rock_BacklogMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=rock_TwoMetalRoofingBusinessesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: