Other Balance Sheet Items (Other Long Term Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
prepaid registry fees, non current	$ 8.7	$ 9.1
Operating Lease, Right-of-Use Asset	5.6	7.2
Restricted Cash	5.3	5.4
Prepaid Expense, Noncurrent	5.2	6.6
Other Assets, Miscellaneous, Noncurrent	3.1	2.3
Other Assets, Noncurrent	$ 27.9	$ 30.6