Leases (Supplemental Balance Sheet Information Related To Leases) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	OTHER ASSETS	OTHER ASSETS
Right-of-use assets	$ 55,845	$ 55,897
Liabilities
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and other current liabilities	Accrued expenses and other current liabilities
Current lease liabilities	$ 8,060	$ 7,661
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Long-term lease liabilities	$ 51,690	$ 51,336
Total lease liabilities	$ 59,750	$ 58,997
Weighted-average remaining lease term	11 years 10 months 24 days	12 years 6 months
Weighted-average discount rate	9.40%	9.22%