Income taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|---|---|
| Deferred tax assets: | ||||
| Net operating loss carryforwards | $ 46,998 | $ 44,565 | ||
| Outside basis differences for U.S. partnerships | 7,941 | 8,656 | ||
| Operating lease liabilities | 4,076 | 4,695 | ||
| Deferred revenue | 800 | 782 | ||
| Deferred compensation | 86 | 623 | ||
| State taxes | 39 | 44 | ||
| Stock options | 0 | 0 | ||
| Other | 2,099 | 939 | ||
| Valuation allowance | (46,459) | (41,646) | $ (33,810) | $ (34,990) |
| Net deferred tax assets | 15,580 | 18,658 | ||
| Deferred tax liabilities: | ||||
| Property and equipment | (5,729) | (6,943) | ||
| Convertible Notes | (3,403) | (4,366) | ||
| Operating lease right-of-use assets | (2,888) | (3,348) | ||
| Intangible assets | (3,106) | (3,079) | ||
| Stock options | (1,438) | (1,915) | ||
| Net deferred tax liabilities | (16,564) | (19,651) | ||
| Net deferred taxes | $ (984) | $ (993) |
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from state taxes. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from financing arrangements. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from operating lease right of use assets. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences arising from U.S. partnership basis differences. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax liabilities attributable to deductible temporary differences from share-based compensation. No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from operating lease liabilities. No definition available.
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