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Income Taxes | 9 Months Ended
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Sep. 30, 2019
Income Tax Disclosure [Abstract] |
Income Taxes | (4) Income Taxes Fastenal files income tax returns in the United States federal jurisdiction, all states, and various local and foreign jurisdictions. With limited exceptions, we are no longer subject to income tax examinations by taxing authorities for taxable years before 2016 in the case of United States federal examinations, and 2015 in the case of foreign, state, and local examinations. During the first nine months of 2019, there were no material changes in unrecognized tax benefits.

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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -URI http://asc.fasb.org/topic&trid=2144680 + Details
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