XML 53 R37.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Acquisitions (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2015
Business Acquisition [Line Items] |
Schedule of Business Combination Costs | All acquisition related costs (including the gains recognized as a result of the change in fair value of the earn-out obligation) consisted of the following for the years ended December 31 (in thousands):
| 2015 |  | 2014 |  | 2013
Selling, general and administrative costs | $ | 732 |  |  | $ | (1,594 | ) |  | $ | (34 | )
Cost of sales | 230 |  |  | 206 |  |  | 685 |
Total acquisition related costs | $ | 962 |  |  | $ | (1,388 | ) |  | $ | 651 |
2013 Acquisitions |
Business Acquisition [Line Items] |
Schedule of allocation of purchase consideration | The allocation of purchase consideration to the assets acquired and liabilities assumed during 2013 are as follows (in thousands):
Working capital | $ | 2,665 |
Property, plant, and equipment | 153 |
Acquired intangible assets | 2,170 |
Goodwill | 2,466 |
Fair value of purchase consideration | $ | 7,454 |
Schedule of Acquired Intangible Assets | The intangible assets acquired in this acquisition consisted of the following (in thousands):
| Fair Value |  | Estimated Useful Life
Trademarks | $ | 640 |  |  | Indefinite
Technology | 260 |  |  | 15 Years
Customer relationships | 1,130 |  |  | 15 Years
Non-compete agreements | 140 |  |  | 5 Years
Total | $ | 2,170 |  |  |

X
- Definition Schedule of Business Combination Costs [Table Text Block] + References No definition available. + Details
Name: | rock_ScheduleofBusinessCombinationCostsTableTextBlock
Namespace Prefix: | rock_
Data Type: | nonnum:textBlockItemType
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 No definition available. + Details
Name: | us-gaap_BusinessAcquisitionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of a material business combination completed during the period, including background, timing, and recognized assets and liabilities. This table does not include leveraged buyouts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1486-128463 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
Name: | us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of finite-lived intangible assets acquired as part of a business combination or through an asset purchase, by major class and in total, including the value of the asset acquired, any significant residual value (the expected value of the asset at the end of its useful life) and the weighted-average amortization period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275 + Details
Name: | us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=rock_AcquisitionsDuring2013Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |