Description of the Business and Significant Accounting Policies (Cash and Equivalents, and Restricted Cash and Equivalents) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Description of the Business and Significant Accounting Policies
Restricted Cash and Cash Equivalents	$ 5.5	$ 5.5	$ 5.5	$ 5.5	$ 5.5	$ 5.5
Restricted Cash and Cash Equivalents, Asset, Statement of Financial Position [Extensible List]	Other assets	Other assets	Other assets	Other assets	Other assets	Other assets