Summary of Significant Accounting Policies - Accounts Receivable, net and Inventories (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Bad debt expense | $ 100 | $ 100 | |
| Recovery recognized related to bad debt expense previously written off | $ 1,100 | ||
| Inventory, Net [Abstract] | |||
| Finished goods | 9,815 | 17,612 | |
| Raw materials | 152 | 243 | |
| Parts, supplies and other | 32,382 | 30,441 | |
| Total Inventories | 42,349 | 48,296 | |
| Inventory depreciation | $ 2,000 | $ 4,500 | |
| Accounts receivable | Customer concentration | |||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | |||
| Percentage of concentration risk | 20.00% | 18.00% | |
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- Definition Inventory, Accumulated Depreciation No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date for elements of machinery or equipment held for the purpose of replacing similar parts in the course of repair or maintenance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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