Accrued Liabilities Long-term liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued Liabilities [Abstract]
Operating Lease, Liability, Noncurrent	$ 39,588	$ 41,019
Accrued Employee Benefits	1,180	1,183
Accrued Rent	1,427	1,462
Liabilities for contracts	303	337
Finance Lease, Liability, Noncurrent	2,330	2,388
Contract with Customer, Liability, Noncurrent	693	864
Other Accrued Liabilities, Noncurrent	589	582
OTHER LONG-TERM LIABILITIES	$ 46,110	$ 47,835