XML 22 R25.htm IDEA: XBRL DOCUMENT
v3.19.3

Revenue - Percentages of Sales by Product Line (Details) - Product Line - Sales | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 100.00% | 100.00% | 100.00% | 100.00%
Fasteners |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 33.70% | 34.70% | 34.30% | 35.10%
Tools |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 10.20% | 10.10% | 10.00% | 10.10%
Cutting tools |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 5.70% | 5.70% | 5.80% | 5.70%
Hydraulics & pneumatics |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 6.80% | 6.70% | 6.90% | 6.90%
Material handling |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 5.90% | 5.70% | 5.90% | 5.80%
Janitorial supplies |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 8.00% | 7.80% | 7.70% | 7.60%
Electrical supplies |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 4.60% | 4.60% | 4.70% | 4.60%
Welding supplies |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 4.20% | 4.10% | 4.20% | 4.10%
Safety Supplies |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 18.20% | 17.30% | 17.60% | 17.00%
Other |  |  |  |
Percentage of Sales by Product Line [Line Items] |  |  |  |
Percentage of sales | 2.70% | 3.30% | 2.90% | 3.10%

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

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_ProductConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_FastenersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_ToolsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_CuttingToolsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_HydraulicsAndPneumaticsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_MaterialHandlingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_JanitorialSuppliesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_ElectricalSuppliesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_WeldingSuppliesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=fast_SafetySuppliesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_ProductAndServiceOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |