Leases (Lease Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Operating lease right-of-use assets	$ 15,127	$ 17,069
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Financing lease right-of-use assets	$ 4,539	$ 5,512
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Total Lease Assets	$ 19,666	$ 22,581
Liabilities
Financing lease liabilities - current	$ 902	$ 860
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities, Current	Accrued Liabilities, Current
Operating lease liabilities - current	$ 2,515	$ 2,454
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities, Current	Accrued Liabilities, Current
Financing lease liabilities - long-term	$ 4,332	$ 5,014
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Operating lease liabilities - long-term	$ 13,272	$ 15,278
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Total Lease Liabilities	$ 21,021	$ 23,606