Lease Obligations - Summary of lease-related assets and liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Assets
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property and equipment, net of accumulated depreciation of $387,375 and $380,465, respectively
Operating lease right-of-use assets	$ 40,396	$ 35,012
Finance lease right-of-use assets	4,069	2,363
Total right-of-use lease assets	44,465	37,375
Current
Operating lease obligations	10,472	9,237
Finance lease obligations	2,168	2,039
Total current obligations	12,640	11,276
Non-current
Operating lease obligations	29,897	25,775
Finance lease obligations, net of current maturities	1,645	314
Total non-current obligations	31,542	26,089
Total lease obligations	$ 44,182	$ 37,365