XML 77 R65.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Segment Information (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) segment | Jun. 30, 2016 USD ($)
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Number of reportable segments | segment |  |  | 3 |
Net sales: | $ 247,627 | $ 265,738 | $ 454,232 | $ 503,409
Income from operations: | 61,825 | 68,843 | 111,080 | 122,993
Unallocated Corporate Expenses | (4,538) | (8,635) | (13,803) | (14,738)
Total income from operations | 24,930 | 28,576 | 34,609 | 46,337
Residential Products |  |  |  |
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Net sales: | 127,252 | 119,965 | 231,803 | 220,112
Income from operations: | 22,579 | 20,725 | 38,220 | 32,956
Industrial and Infrastructure Products |  |  |  |
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Net sales: | 57,926 | 81,380 | 108,644 | 161,397
Income from operations: | 3,397 | 6,190 | 3,360 | 9,516
Renewable Energy & Conservation |  |  |  |
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Net sales: | 62,763 | 64,766 | 114,555 | 122,640
Income from operations: | 3,492 | 10,296 | 6,832 | 18,603
Intersegment Elimination |  |  |  |
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Net sales: | (314) | (373) | (770) | (740)
Intersegment Elimination | Industrial and Infrastructure Products |  |  |  |
Segment Reporting, Other Significant Reconciling Item [Line Items] |  |  |  |
Net sales: | $ 57,612 | $ 81,007 | $ 107,874 | $ 160,657

X
- Definition Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1,2) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_GrossProfit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NumberOfReportableSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The net result for the period of deducting operating expenses from operating revenues. + References No definition available. + Details
Name: | us-gaap_OperatingIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_OtherCostAndExpenseOperating
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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 No definition available. + Details
Name: | us-gaap_SegmentReportingOtherSignificantReconcilingItemLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=rock_ResidentialProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=rock_IndustrialAndInfrastructureProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=rock_RoughBrothersManufacturingInc.RBIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |