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Document Fiscal Period Focus Accrued property, franchise, motor fuel and other taxes Customer [Domain] Legal Matters and Contingencies [Text Block] Document Fiscal Year Focus Amendment Flag Dividends payable - noncurrent The amount of dividends payable classified as noncurrent. Common Stock [Member] us-gaap_LineOfCreditFacilityExpirationPeriod Line of Credit Facility, Expiration Period (Year) Subsequent Events [Text Block] Accrued expenses and other current liabilities Total Document Period End Date Building [Member] Nonrelated Party [Member] Long-Lived Asset, Class [Domain] Dividends payable Legal Entity [Axis] Accrued employee liabilities Related Party [Member] Significant Accounting Policies [Text Block] us-gaap_ShortTermLeaseCost Short-Term Lease, Cost Warehouse Space [Member] Represents the warehouse space. 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Loss Contingencies [Table] Entity Address, State or Province Statement of Stockholders' Equity [Abstract] Inventory, Current [Table] Entity Address, City or Town us-gaap_InterestExpenseNonoperating Interest expense Retained earnings (accumulated deficit) Leverage Ratio 5 [Member] The fifth leverage ratio. Entity Address, Address Line One Statement of Cash Flows [Abstract] City Area Code us-gaap_RevenueRemainingPerformanceObligationPercentage Revenue, Remaining Performance Obligation, Percentage Local Phone Number Entity Address, Postal Zip Code Revenue from Contract with Customer [Text Block] Derivative [Table] Title of 12(b) Security Equity Components [Axis] Security Exchange Name Trading Symbol Regulated fixed price future commitments, included in other current assets (in thousand barrels) Class of Stock [Axis] Base Rate [Member] Equity Component [Domain] Variable Rate [Axis] Variable Rate [Domain] Revenue from non-contractual arrangements Entity Common Stock, Shares Outstanding us-gaap_DerivativeAssetFairValueGrossLiability Regulated fixed price future commitments, included in other current assets (in thousand barrels) Additional Paid-in Capital [Member] Retained Earnings [Member] Earnings Per Share [Text Block] Cost of goods sold Cost of goods sold Cost of goods sold Other current assets Total Change in inventory reserve Change in Accounting Method for Inventory [Member] Represents the change in accounting method for inventory. Property, plant and equipment, net Weighted average shares outstanding Noncash interest expense ff_IncreaseDecreaseInDividendsPayable Dividends payable Represents the amount of increase (decrease) in dividends payable. ff_DistributionExpenses Distribution Represents the amount of distribution expense during the period. Change in allowance for credit losses Other Income and Other Expense Disclosure [Text Block] Subsequent Event [Table] Employment tax credit Amount of employment tax credit, classified as noncurrent. Other expense, net Change in Accounting Principle, Type [Axis] Common stock, par value (in dollars per share) Future [Member] us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue Stock based compensation Basis of Accounting, Policy [Policy Text Block] Previously Reported [Member] Derivative Contract [Domain] Long-Lived Asset, Class [Axis] Total Assets Total Assets Noncurrent deferred income taxes Cash and cash equivalents Collateralization of derivative instruments, net of fair value Represents the cash offset of a derivative asset subject to master netting arrangement collateral obligation to return. 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Tax Credit Carryforward [Table] Non-bill and Hold Revenue [Member] Information pertaining to non-bill and hold revenue. Interest income Inventory Disclosure [Text Block] Schedule of Long-Term Debt Instruments [Table Text Block] us-gaap_GainLossOnSaleOfPropertyPlantEquipment Gain on disposal of property and equipment Finished goods Shipping and Handling [Member] ff_ChangeInFairValueOfDerivativeInstrumentsAndMarketableSecurities Change in fair value of derivative instruments The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments in marketable securities and derivative instruments held at each balance sheet date and included in earnings for the period. us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number (in shares) Inventory, net Total inventory Bill and Hold Arrangements [Member] Bill and hold arrangements. Loss before taxes us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest Net loss before income taxes Loss before taxes Additional paid in capital Deferred revenue us-gaap_IncreaseDecreaseInContractWithCustomerLiability Increase (Decrease) in Contract with Customer, Liability Debt Disclosure [Text Block] Total stockholders' equity Total stockholders’ equity Balance Balance Leverage Ratio1 [Member] The first leverage ration. Leverage Ratio 2 [Member] The second leverage ratio. Work in process Leverage Ratio 3 [Member] The third leverage ratio. Leverage Ratio 4 [Member] The fourth leverage ratio. 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