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Derivative Instruments (Narrative) (Details) | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Feb. 28, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jun. 30, 2021 USD ($) | Mar. 31, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Derivative |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 5.10% | 4.20% |  |  | 4.20% |  | 5.10%
Amount of derivaitve cash flow hedge to be repcognized in the next 12 months |  |  |  |  |  | $ 2,400,000 | $ 5,700,000 |
Repayments of Secured Debt |  |  |  |  |  | 200,000,000 | 100,028,000 |
Amortization of Debt Issuance Costs |  |  | $ 1,337,000 |  | $ 1,031,000 | 5,368,000 | 2,062,000 |
Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 8,500,000 |  |  | 8,500,000 |  |
Not Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 1,063,000 | 272,000 |  |  | 272,000 |  | $ 1,063,000
Other long-term obligations | Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 5,700,000 |  |  | 5,700,000 |  |
Other accrued liabilities | Separated Host Financial Instrument, Fair Value Option |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  |  | 2,800,000 |  |  | 2,800,000 |  |
2018 Credit Agreement | Term Loan Facility |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Repayments of Secured Debt |  | $ 500,000,000 | 50,000,000.0 |  |  | 200,000,000 |  |
Amortization of Debt Issuance Costs | $ 900,000 |  | $ 300,000 |  |  | $ 1,200,000 |  |
Foreign currency derivatives |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, notional amount |  | 71,000,000.0 | 80,500,000 |  |  | 80,500,000 |  | 71,000,000.0
Commodity derivative contracts |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, notional amount |  | 61,300,000 | 38,400,000 |  |  | 38,400,000 |  | 61,300,000
Unrealized (loss) gain in other comprehensive income |  |  |  |  |  | $ 12,800,000 |  | $ 2,200,000
Derivative Instruments Not Designated as Hedging Instruments, Loss |  |  |  |  |  | 900,000 |  |
Commodity derivative contracts | Not Designated as Hedging Instrument | Interest expense |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  |  |  |  | (242,000) | (114,000) |
Commodity derivative contracts | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 13,769,000 | $ 844,000 |  |  | 844,000 |  | 13,769,000
Commodity derivative contracts | Other long-term obligations | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | 1,898,000 | 0 |  |  | 0 |  | 1,898,000
Commodity derivative contracts | Other accrued liabilities | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | 888,000 | 0 |  |  | 0 |  | 888,000
Interest rate swap contract |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent |  |  |  | $ 11,000,000.0 |  | 1,900,000 |  |
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 |  |  | 289,000 |  | 1,521,000 | 1,285,000 | 1,315,000 |
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 |  |  |  |  |  | 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 |  | 6,903,000
Interest rate swap contract | Other accrued liabilities | Cash Flow Hedging | Designated as Hedging Instrument |  |  |  |  |  |  |  |
Derivative |  |  |  |  |  |  |  |
Derivative liability fair value |  | $ 4,080,000 | 844,000 |  |  | 844,000 |  | $ 4,080,000
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% |  | 4.85%

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