XML 70 R57.htm IDEA: XBRL DOCUMENT
v3.19.1

Business Segment (Sales by Major Product Line) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Revenue from External Customer |  |
Net Sales | $ 626,969 | $ 536,377
Rail Products |  |
Revenue from External Customer |  |
Net Sales | 188,590 | 155,870
Rail Technologies |  |
Revenue from External Customer |  |
Net Sales | 130,934 | 100,257
Piling and Fabricated Bridges Products |  |
Revenue from External Customer |  |
Net Sales | 102,246 | 105,924
Protective Coating and Measurement Systems |  |
Revenue from External Customer |  |
Net Sales | 89,026 | 67,766
Test , Inspection and Threading Services |  |
Revenue from External Customer |  |
Net Sales | 59,766 | 50,683
Precast Concrete Products |  |
Revenue from External Customer |  |
Net Sales | $ 56,407 | $ 55,877

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_EntityWideInformationRevenueFromExternalCustomerLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 32 -Paragraph 2A -URI http://asc.fasb.org/extlink&oid=82859839&loc=SL82860478-203043 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130539-203045 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130543-203045 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130545-203045 + Details
Name: | us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_RailDistributionProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_RailTechnologiesProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_PilingProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_CxtConcreteBuildingProductsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_TestAndInspectionServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ProductOrServiceAxis=fstr_ProtectiveCoatingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |