Organization and Significant Accounting Policies - Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net income	$ 120.7	$ 101.2	$ 285.2	$ 249.4
Add back interest expense, net of tax attributable to assumed conversion of senior convertible notes	3.0	2.8	9.6	8.3
Net income - diluted	$ 123.7	$ 104.0	$ 294.8	$ 257.7
Net income per common share
Basic net income per share (in USD per share)	$ 0.31	$ 0.26	$ 0.74	$ 0.64
Diluted net income per share (in USD per share)	$ 0.29	$ 0.24	$ 0.69	$ 0.60
Basic weighted average shares outstanding (in shares)	386.6	389.8	386.7	390.4
Diluted weighted average shares outstanding (in shares)	426.8	425.8	428.3	428.0
Restricted stock units and performance stock units
Net income per common share
Dilutive potential common stock outstanding (in shares)	1.0	0.5	1.1	0.9
Warrants
Net income per common share
Dilutive potential common stock outstanding (in shares)	11.6	8.6	11.8	9.8
Senior convertible notes
Net income per common share
Dilutive potential common stock outstanding (in shares)	27.6	26.9	28.7	26.9