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Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Contingent consideration arrangement | $ 6,200 |
Contingent consideration, gain (loss) due to change in value | 16,600 |
Contingent consideration, settlements | 300 |
Asset retirement obligation capitalized | 2,358 | $ 5,935
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Contingent consideration arrangement | 6,200 |
Asset retirement obligation capitalized | 2,400 |
Prepaid Expenses and Other Current Assets |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Contingent consideration arrangement | 1,100 |
Other Noncurrent Assets |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Contingent consideration arrangement | $ 5,100 |

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- Definition Amount of asset retirement obligations incurred during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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