XML 20 R60.htm IDEA: XBRL DOCUMENT
v3.20.1

Long-Term Debt - Narrative (Details) | Apr. 30, 2019 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
--- | --- | --- | ---
Revolving credit facility |  |  |
Line of Credit Facility |  |  |
Line of credit facility, amount outstanding |  | $ 40,688,000 | $ 33,868,000
Term loan |  |  |
Line of Credit Facility |  |  |
Line of credit facility, amount outstanding |  | 23,125,000 | $ 23,750,000
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company |  |  |
Line of Credit Facility |  |  |
Line of credit facility, maximum borrowing capacity | $ 195,000,000 |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility |  |  |
Line of Credit Facility |  |  |
Line of credit facility, maximum borrowing capacity | 140,000,000 |  |
Potential increase to borrowing capacity | $ 50,000,000 |  |
Line of credit facility, current borrowing capacity |  | 98,753,000 |
Debt instrument term | 5 years |  |
Maximum growth leverage ratio | 3.25 |  |
Maximum growth leverage ratio during acquisition period | 3.50 |  |
Minimum consolidated fixed charge coverage ratio | 1.25 |  |
Minimum working capital to revolving facility usage ratio | 1.40 |  |
Liquidity covenant | $ 25,000,000 |  |
Acquisition consideration threshold, per acquisition | 50,000,000 |  |
Aggregate acquisition threshold for four consecutive periods where acquisitions occurred | 50,000,000 |  |
Aggregate acquisition consideration threshold | 100,000,000 |  |
Line of credit facility, amount outstanding |  | $ 559,000 |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Foreign Sublimit |  |  |
Line of Credit Facility |  |  |
Line of credit facility, maximum borrowing capacity | $ 25,000,000 |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Euro-rate |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Euro-rate | Maximum |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 2.25% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Euro-rate | Minimum |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 1.25% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Base Rate | Maximum |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 1.25% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Base Rate | Minimum |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 0.25% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | Overnight Bank Funding Rate |  |  |
Line of Credit Facility |  |  |
Debt instrument, basis spread on variable rate | 0.50% |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Term loan | Term Loan |  |  |
Line of Credit Facility |  |  |
Line of credit facility, current borrowing capacity | $ 25,000,000 |  |

X
- Definition Acquisition Consideration Threshold + References No definition available. + Details
Name: | fstr_AcquisitionConsiderationThreshold
Namespace Prefix: | fstr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Aggregate Acquisition Consideration Threshold + References No definition available. + Details
Name: | fstr_AggregateAcquisitionConsiderationThreshold
Namespace Prefix: | fstr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Aggregate Acquisition Consideration Threshold, Per Period + References No definition available. + Details
Name: | fstr_AggregateAcquisitionConsiderationThresholdPerPeriod
Namespace Prefix: | fstr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line of Credit Facility, Potential Increase To Borrowing Capacity + References No definition available. + Details
Name: | fstr_LineOfCreditFacilityPotentialIncreaseToBorrowingCapacity
Namespace Prefix: | fstr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | fstr_LiquidityCovenant
Namespace Prefix: | fstr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Maximum Growth Leverage Ratio + References No definition available. + Details
Name: | fstr_MaximumGrowthLeverageRatio
Namespace Prefix: | fstr_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum Growth Leverage Ratio During Acquisition Period + References No definition available. + Details
Name: | fstr_MaximumGrowthLeverageRatioDuringAcquisitionPeriod
Namespace Prefix: | fstr_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Minimum Consolidated Fixed Charge Coverage Ratio + References No definition available. + Details
Name: | fstr_MinimumConsolidatedFixedChargeCoverageRatio
Namespace Prefix: | fstr_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Minimum Working Capital to Revolving Facility Usage Ratio + References No definition available. + Details
Name: | fstr_MinimumWorkingCapitalToRevolvingFacilityUsageRatio
Namespace Prefix: | fstr_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
Name: | us-gaap_LineOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_SecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=fstr_PncBankN.a.BankOfAmericaN.a.WellsFargoBankN.a.CitizensBankOfPennsylvaniaAndBranchBankingAndTrustCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=fstr_ForeignSublimitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_EurodollarMember
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: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=fstr_OvernightBankFundingRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=fstr_TermLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |