CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 595.6	$ 586.7	$ 449.3
Other comprehensive loss:
Reclassification adjustments for derivatives, net of tax	0.0	0.0	2.5
Pension and other postretirement adjustments, net of tax	(7.4)	18.3	17.0
Cumulative translation adjustment	87.8	(74.9)	(75.6)
Other comprehensive income (loss)	80.4	(56.6)	(56.1)
Comprehensive income	676.0	530.1	393.2
Comprehensive loss attributable to noncontrolling interest	0.5	0.2	0.0
Comprehensive income attributable to IDEX	$ 676.5	$ 530.3	$ 393.2