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Long-Term Debt (Narrative) (Details) - USD ($) |  |  |  |  | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 01, 2020 | Dec. 31, 2019 | Sep. 13, 2019 | Aug. 27, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Aug. 31, 2019 | Apr. 25, 2017
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  | $ 13,200,000 | $ 10,700,000 |  |
Dividend restrictions |  |  |  |  | The credit agreement contains restrictions on certain payments, including dividends, when availability under the credit agreement is less than or equal to the greater of $100 million and 25% of the lesser of the revolving commitments and the borrowing base and our fixed charge coverage ratio is less than 1 to 1.0 (unless availability under the credit agreement is greater than $100 million and 40% of the lesser of the revolving commitments and the borrowing base). As of March 31, 2020 and December 31, 2019, our ability to make restricted payments was limited as our availability under the borrowing base was less than $100 million, at $91.3 million, while our fixed charge coverage ratio was less than 1.0 to 1.0, at 0.91 subject to an annual available basket of up to $25 million which remains unused for the current period. As of March 31, 2020, the Company had a shortfall of approximately $53.9 million of our net income and retained earnings subject to such restrictions before the fixed charge coverage ratio would exceed 1.0 to 1.0. |  |  |
Fixed charge coverage ratio |  |  |  |  | 1.21 |  |  |
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 |  |  |  |  | 0.33 |  |  |
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% |  |  |
Dividend restrictions, fixed charge coverage ratio |  |  |  |  | 1.0 |  |  |
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% |  |  |
Interest period one (in months) |  |  |  |  | 1 month |  |  |
Interest period two (in months) |  |  |  |  | 2 months |  |  |
Interest period three (in months) |  |  |  |  | 3 months |  |  |
Interest period four (in months) |  |  |  |  | 6 months |  |  |
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% |  |  |
ABL facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  |  |  | $ 325,000,000 |
ABL facility | LIBOR | Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 1.50% |  |  |
ABL facility | LIBOR | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 2.00% |  |  |
ABL facility | Alternate Base Rate | Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 0.50% |  |  |
ABL facility | Alternate Base Rate | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 1.00% |  |  |
Term facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  |  |  | 250,000,000.0 |
Proceeds borrowed from credit facility |  | $ 50,000,000 |  | $ 200,000,000 |  |  |  |
Term of facility |  |  |  | 4 years |  |  |  |
Repayments of debt |  |  |  | $ 57,000,000 |  |  |  |
Asset-based loan facility, portion included in current maturities |  | $ 250,000,000.0 |  |  | $ 237,500,000 |  |  |
Quarterly principal payments | $ 12,500,000 |  |  |  |  |  |  |
Term facility | LIBOR | Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 2.50% |  |  |
Term facility | LIBOR | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 2.75% |  |  |
Term facility | Alternate Base Rate | Minimum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 1.50% |  |  |
Term facility | Alternate Base Rate | Maximum |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread over variable rate (percent) |  |  |  |  | 1.75% |  |  |
Uncommitted incremental facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  |  |  |  |  | 150,000,000 |
Letters of credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Line of credit facility, sublimit |  |  |  |  |  |  | $ 100,000,000 |
Asset Based Loan Facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Remaining loan amount available |  |  |  |  | $ 168,300,000 |  |  |
4.75% senior notes due 2029 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Senior notes, principal amount |  |  | $ 500,000,000 |  |  |  |  |
Interest rate |  |  |  |  | 4.75% |  |  |
4.75% senior notes due 2029 | ABL facility | Line of Credit |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Interest rate |  |  | 4.75% |  | 4.75% |  |  |
5.625% Senior Notes Due 2027 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Senior notes, principal amount |  |  |  |  |  |  |  | $ 300,000,000
Interest rate |  |  |  |  | 5.625% |  |  | 5.625%
Asset Based Loan Facility |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Asset-based loan facility, portion included in current maturities |  |  |  |  | $ 0 |  |  |
Term loan due 2023 | Senior Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Redemption of aggregate principal amount |  |  | $ 500,000,000 |  |  |  |  |

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