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Derivative Instruments (Narrative) (Details) | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Feb. 28, 2021 USD ($) | Dec. 31, 2020 USD ($) | Sep. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Sep. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($)
Derivative |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 5.10% | 4.20% |  |  |  | 4.20% |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent |  |  | $ 3,729,000 |  | $ 2,826,000 |  | $ 27,556,000 | $ (25,717,000)
Amount of derivaitve cash flow hedge to be repcognized in the next 12 months |  |  |  |  |  |  | 7,000,000 | 8,000,000
Repayments of Secured Debt |  |  |  |  |  |  | 300,000,000 | 249,214,000
Amortization of Debt Issuance Costs |  |  | 1,707,000 |  | 1,032,000 |  | 7,075,000 | 3,094,000
Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 7,600,000 |  |  |  | 7,600,000 |
Not Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 1,063,000 | 1,077,000 |  |  |  | 1,077,000 |
Other long-term obligations | Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 5,100,000 |  |  |  | 5,100,000 |
Other accrued liabilities | Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 2,500,000 |  |  |  | 2,500,000 |
2018 Credit Agreement | Term Loan Facility |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Repayments of Secured Debt |  | $ 500,000,000 | 100,000,000 |  |  |  | 300,000,000 |
Amortization of Debt Issuance Costs | $ 900,000 |  | $ 500,000 |  |  |  | $ 1,800,000 |
Foreign currency derivatives |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, notional amount |  | 71,000,000 | 102,900,000 |  |  |  | 102,900,000 |
Commodity derivative contracts |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, notional amount |  | 61,300,000 | 28,900,000 |  |  |  | 28,900,000 |
Pre-tax net unrealized gain (loss) within Accumulated Other Comprehensive Income |  |  |  | $ (2,200,000) |  |  | $ 12,300,000 |
Derivative Instruments Not Designated as Hedging Instruments, Loss |  |  | $ 200,000 |  |  |  | 700,000 |
Commodity derivative contracts | Not Designated as Hedging Instrument | Interest expense |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  |  |  |  | (682,000) | (321,000)
Commodity derivative contracts | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 13,769,000 | 848,000 |  |  |  | 848,000 |
Commodity derivative contracts | Other long-term obligations | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | 1,898,000 | 0 |  |  |  | 0 |
Commodity derivative contracts | Other accrued liabilities | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | 888,000 | 0 |  |  |  | 0 |
Interest rate swap contract |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent |  |  |  |  |  | $ 11,000,000 | 1,700,000 |
Derivative, Notional Amount |  |  |  |  | 500,000,000 |  |  | 500,000,000
Interest rate swap contract | Designated as Hedging Instrument | Interest expense |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  | 285,000 |  | 1,537,000 |  | 1,571,000 | 2,852,000
Interest rate swap contract | Not Designated as Hedging Instrument | Interest expense |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  |  |  |  | 866,000 | 0
Interest rate swap contract | Not Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Notional Amount |  | 250,000,000 |  |  |  |  |  |
Interest rate swap contract | Other long-term obligations | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | 6,903,000 | 0 |  |  |  | 0 |
Interest rate swap contract | Other accrued liabilities | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 4,080,000 | 848,000 |  |  |  | 848,000 |
Interest rate swap contract 2 |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  |  |  | $ 500,000,000 |  |  | $ 500,000,000
Interest Rate Swap Four |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  | $ 250,000,000 |  |  |  | $ 250,000,000 |
Scenario, Plan |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 4.85% | 3.95% |  |  |  | 3.95% |

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