General - Leases - Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Components of lease assets and liabilities
Operating lease right-of-use assets	$ 30,411
Operating Lease, Right-of-Use Asset, Statement of Financial Position	Other long-term assets
Current operating lease liabilities	$ 10,994
Operating Lease, Liability, Current, Statement of Financial Position	Accrued liabilities
Long-term operating lease liabilities	$ 32,063
Operating Lease, Liability, Noncurrent, Statement of Financial Position	Deferred credits and other long-term liabilities
Total operating lease liabilities	$ 43,057
Operating Lease, Liability, Statement of Financial Position	us-gaap:AccruedLiabilitiesCurrent us-gaap:DeferredCreditsAndOtherLiabilitiesNoncurrent
Finance lease assets	$ 9,637
Finance Lease, Right-of-Use Asset, Statement of Financial Position	Property and equipment, net
Current finance lease liabilities	$ 4,493
Finance Lease, Liability, Current, Statement of Financial Position	Current debt, finance lease and deferred financing obligations
Long-term finance lease liabilities	$ 8,524
Finance Lease, Liability, Noncurrent, Statement of Financial Position	Long-term debt, finance lease and deferred financing obligations
Total finance lease liabilities	$ 13,017	$ 16,400
Total lease liabilities	$ 56,074