Treasury Stock Transactions (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Treasury Stock, Value [Abstract]
Number of Treasury Shares Repurchased			1,800,000	2,400,000	3,100,000
Cost of Shares Repurchased	[1]	$ 47.0	$ 57.4	$ 100.6	$ 94.9
Commissions Paid on Stock Repurchases		0.1	0.1	0.1	0.1
Share Repurchases Excise Tax		$ 0.4	$ 0.0	$ 0.5	$ 0.0

[1] 1Includes $0.1 million of commissions for the three and six months ended June 30, 2023 and $0.1 million of commission for the three and six months ended June 30, 2022. There was $0.4 million and $0.5 million of excise tax for the three and six months ended June 30, 2023, respectively. There were no excise taxes during the three and six months ended June 30, 2022.