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Long-Term Debt (Narrative) (Details) - USD ($) |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 01, 2020 | Aug. 27, 2019 | Dec. 31, 2020 | Sep. 13, 2019 | Aug. 31, 2019 | Apr. 25, 2017
Debt Instrument [Line Items] |  |  |  |  |  |
Fixed charge coverage ratio |  |  | 0.90 |  |  |
Fixed charge coverage ratio threshold, percentage of aggregate facility commitments and borrowing base |  |  | 17.50% |  |  |
Fixed charge coverage ratio threshold, amount of aggregate facility commitments and borrowing base |  |  | $ 70,000,000 |  |  |
Secured debt to EBITDA ratio |  |  | 0.29 |  |  |
Shortfall of net income and retained earnings |  |  | $ 82,700,000 |  |  |
Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Fixed charge coverage ratio |  |  | 1.0 |  |  |
Period for fixed charge coverage ratio threshold (in days) |  |  | 3 days |  |  |
Dividend restriction threshold as amount of availability |  |  | $ 100,000,000 |  |  |
Dividend restriction threshold as a percentage of revolving commitments and borrowing base |  |  | 25.00% |  |  |
Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Secured debt to EBITDA ratio |  |  | 4.5 |  |  |
Dividend restriction threshold as a percentage of revolving commitments and borrowing base with consideration of fixed charge coverage ratio |  |  | 40.00% |  |  |
Federal Funds Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 0.50% |  |  |
LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 1.00% |  |  |
Cash |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 100.00% |  |  |
Credit Card Receivables |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 90.00% |  |  |
Investment Grade Accounts |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 90.00% |  |  |
Other Accounts |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 85.00% |  |  |
Midstream Refined Products Inventory |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 80.00% |  |  |
Refined Retail Products Inventory |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 75.00% |  |  |
Retail Merchandise Inventory |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Percentage of asset available to borrow against |  |  | 70.00% |  |  |
Percentage of net orderly liquidation value available to borrow against |  |  | 85.00% |  |  |
Secured Debt |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | $ 325,000,000 |
Secured Debt | LIBOR | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 1.50% |  |  |
Secured Debt | LIBOR | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 2.00% |  |  |
Secured Debt | Alternative Base Rate | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 0.50% |  |  |
Secured Debt | Alternative Base Rate | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 1.00% |  |  |
Term Loan |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | 200,000,000 |
Proceeds from lines of credit |  | $ 200,000,000 |  |  |  |
Debt instrument term |  | 4 years |  |  |  |
Repayments of long-term debt |  | $ 57,000,000 |  |  |  |
Additional term loan |  |  | $ 50,000,000 |  |  |
Outstanding balance |  |  | $ 212,500,000 |  |  |
Principal payment period | $ 12,500,000 |  |  |  |  |
Term Loan | LIBOR | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 2.50% |  |  |
Term Loan | LIBOR | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 2.75% |  |  |
Term Loan | Alternative Base Rate | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 1.50% |  |  |
Term Loan | Alternative Base Rate | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Spread over variable rate (percent) |  |  | 1.75% |  |  |
Additional Term Loan Available Until December 2019 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | 50,000,000 |
Incremental Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  | 150,000,000 |
ABL Facility |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Additional term loan |  |  | $ 100,000,000 |  |  |
Outstanding under facility |  |  | $ 0 |  |  |
Letter Of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of credit facility, sublimit |  |  |  |  | $ 100,000,000 |
Senior Notes | 5.625% senior notes due 2027 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Senior notes |  |  |  |  |  | $ 300,000,000
Interest rate (percent) |  |  |  |  |  | 5.625%
Senior Notes | Senior Notes 4.75 Percent Due 2029 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Senior notes |  |  |  | $ 500,000,000 |  |
Interest rate (percent) |  |  |  | 4.75% |  |

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