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| | | <ShortName> All Reports </ShortName> |
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| | <File> fast-20200930_lab.xml </File> |
| | <File> fast-20200930_pre.xml </File> |
| | <File> fast9302020ex31.htm </File> |
| | <File> fast9302020ex32.htm </File> |
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| <SupplementalFiles/> |
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| | <BaseTaxonomy> http://xbrl.sec.gov/country/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://fasb.org/us-gaap/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://fasb.org/srt/2020-01-31 </BaseTaxonomy> |
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| <HasCalculationLinkbase> true </HasCalculationLinkbase> |
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