Leases - Supplemental balance sheet information (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Leases
Operating lease assets	$ 108,613	$ 130,454
Other current liabilities	$ 46,419	$ 60,203
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Accrued Liabilities, Current	Other Accrued Liabilities, Current
Operating lease liabilities	$ 66,635	$ 75,142
Total operating lease liabilities	$ 113,054	$ 135,345
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Operating lease liabilities, Other Accrued Liabilities, Current	Operating lease liabilities, Other Accrued Liabilities, Current
Property and equipment, gross	$ 4,395,861	$ 4,431,071
Accumulated depreciation	(3,458,633)	(3,440,185)
Property and equipment, net	937,228	990,886
Other current liabilities	$ 39,060	$ 38,102
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long-term Debt and Capital Lease Obligations, Current	Long-term Debt and Capital Lease Obligations, Current
Other long-term liabilities	$ 20,993	$ 31,104
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term Debt, Excluding Current Maturities	Long-term Debt, Excluding Current Maturities
Total finance lease liabilities	$ 60,053	$ 69,206
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Contract with Customer, Liability, Noncurrent and Other Long Term Liabilities	Contract with Customer, Liability, Noncurrent and Other Long Term Liabilities
Weighted Average Remaining Lease Term: Operating leases	4 years 1 month 6 days	3 years 8 months 12 days
Weighted Average Remaining Lease Term: Finance leases	1 year 6 months	1 year 9 months 18 days
Weighted Average Discount Rate: Operating leases	7.20%	7.20%
Weighted Average Discount Rate: Finance leases	10.00%	10.00%
Property and equipment [Member]
Leases
Property and equipment, gross	$ 175,704	$ 175,704
Accumulated depreciation	(124,081)	(115,469)
Property and equipment, net	$ 51,623	$ 60,235