CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Property, equipment and capitalized software, accumulated depreciation	$ 571.0	$ 529.9
Accumulated amortization	$ 1,261.1	$ 1,173.2
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	175.0	175.0
Common stock, shares issued (in shares)	49.8	49.6
Common stock, shares, outstanding (in shares)	42.9	43.2
Treasury stock, shares (in shares)	6.9	6.3