Description of the Business and Significant Accounting Policies - Cash and Equivalents, and Restricted Cash and Equivalents (Details) - USD ($) $ in Millions	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Description of the Business and Significant Accounting Policies
Restricted Cash and Cash Equivalents	$ 5.6	$ 5.5	$ 5.6	$ 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