| Fair Value Measurements, Recurring and Nonrecurring |
The following tables summarize the carrying amounts, fair values and fair value measurements recorded or disclosed as of December 31, 2018 and 2019, based on the three levels established by ASC 820; Fair Value Measurements and Disclosures (in thousands): | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fair Value Measurements as of December 31, 2018 using: | Assets (Liabilities) | | Carrying Amount | | Fair Value | | Quoted Prices in Active Markets for Identical Assets (Level 1) | | Significant Other Observable Inputs (Level 2) | | Significant Unobservable Inputs (Level 3) | Commodity derivatives contracts | | $ | 55,011 |
| | $ | 55,011 |
| | $ | 55,011 |
| | $ | — |
| | $ | — |
| Interest rate contracts | | $ | (8,126 | ) | | $ | (8,126 | ) | | $ | — |
| | $ | (8,126 | ) | | $ | — |
| Long-term receivables | | $ | 20,844 |
| | $ | 20,844 |
| | $ | — |
| | $ | — |
| | $ | 20,844 |
| Guarantees | | $ | (16,409 | ) | | $ | (16,409 | ) | | $ | — |
| | $ | — |
| | $ | (16,409 | ) | Debt | | $ | (4,270,869 | ) | | $ | (4,224,373 | ) | | $ | — |
| | $ | (4,224,373 | ) | | $ | — |
|
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Fair Value Measurements as of December 31, 2019 using: | Assets (Liabilities) | | Carrying Amount | | Fair Value | | Quoted Prices in Active Markets for Identical Assets (Level 1) | | Significant Other Observable Inputs (Level 2) | | Significant Unobservable Inputs (Level 3) | Commodity derivatives contracts | | $ | (10,222 | ) | | $ | (10,222 | ) | | $ | (10,222 | ) | | $ | — |
| | $ | — |
| Basis derivative agreement | | $ | (17,304 | ) | | $ | (17,304 | ) | | $ | — |
| | $ | (17,304 | ) | | $ | — |
| Long-term receivables | | $ | 20,782 |
| | $ | 20,782 |
| | $ | — |
| | $ | — |
| | $ | 20,782 |
| Guarantees | | $ | (408 | ) | | $ | (408 | ) | | $ | — |
| | $ | — |
| | $ | (408 | ) | Debt | | $ | (4,706,075 | ) | | $ | (5,192,685 | ) | | $ | — |
| | $ | (5,192,685 | ) | | $ | — |
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