Finance Obligation - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Sale Leaseback Transaction [Line Items]
Total operating lease, liabilities	$ 122,311
Short term operating lease obligation	18,778	$ 14,314
Long term operating lease obligation	103,533	99,624
Total finance lease liabilities	10,301
Short term finance lease obligation	1,794	903
Long term finance lease obligation	8,507	4,493
Sale Leaseback Agreements
Sale Leaseback Transaction [Line Items]
Total finance lease liabilities	21,769	23,900
Short term finance lease obligation	7,400	8,000
Long term finance lease obligation	14,400	15,900
Sale Leaseback Agreements | Future Services [Member]
Sale Leaseback Transaction [Line Items]
Short term operating lease obligation	24,700
Long term operating lease obligation	136,300
Total finance lease liabilities	$ 161,000	157,700
Short term finance lease obligation		24,200
Long term finance lease obligation		$ 133,500