Comprehensive Income - Reclassifications from Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accumulated Other Comprehensive Income Loss [Line Items]
Net realized loss	$ (4.6)	$ (5.7)
Reclassifications from Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Reclassifications before tax	0.6	0.6
Income tax benefit	0.2	0.2
Reclassifications, net of tax	0.4	0.4
Reclassifications from Accumulated Other Comprehensive Loss | Interest Rate Collars: Net Realized Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Net realized loss	$ 0.6	$ 0.6