Condensed Consolidated Balance Sheets (UNAUDITED) (Parenthetical) - USD ($) $ in Millions		Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Receivables, allowance for expected losses	[1]	$ 18.1	$ 17.1
Preferred stock, par value		$ 0.01	$ 0.01
Preferred stock, authorized		1,000,000.0	1,000,000.0
Preferred stock, Issued		0	0
Common stock, par value		$ 0.01	$ 0.01
Common stock, Authorized		65,000,000.0	65,000,000.0
Common stock, Issued		37,900,000	36,900,000
Common stock, Outstanding		29,500,000	28,900,000
Treasury stock, Shares		8,400,000	8,000,000.0

[1] As of March 31, 2023, the CECL reserve balance is comprised of a $17.2 million provision for accounts receivable and a $0.9 million provision for unbilled receivables and contract assets. As of December 31, 2022, the CECL reserve balance was comprised of a $16.5 million provision for accounts receivable and a $0.6 million provision for unbilled receivables and contract assets.