| Leases - Right-of-Use Lease Assets and Lease Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | 
|---|---|---|
| Assets | ||
| Operating lease assets | $ 48,239 | $ 48,417 | 
| Finance lease assets | 1,752 | 1,556 | 
| Total leased assets | 49,991 | 49,973 | 
| Current: | ||
| Operating lease liabilities | 15,194 | 11,857 | 
| Finance lease liabilities | 262 | 185 | 
| Noncurrent: | ||
| Operating lease liabilities | 32,019 | 34,908 | 
| Finance lease liabilities | 366 | 315 | 
| Total lease liabilities | $ 47,841 | $ 47,265 | 
| Finance lease asset, balance sheet line item | us-gaap:PropertyPlantAndEquipmentNet | |
| Finance lease liabilities, current, balance sheet line item | us-gaap:AccruedLiabilitiesCurrent | |
| Finance lease liabilities, noncurrent, balance sheet line item | us-gaap:OtherLiabilitiesNoncurrent | 
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- Definition Operating and Finance Lease Liabilities, Total No definition available. 
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- Definition Operating and finance right-of-use lease assets, total No definition available. 
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- References No definition available. 
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Indicates line item in statement of financial position that includes current finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Indicates line item in statement of financial position that includes noncurrent finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount, after accumulated amortization, of right-of-use asset from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Indicates line item in statement of financial position that includes finance lease right-of-use asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- References No definition available. 
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- References No definition available. 
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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