CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 138.5	$ 138.1	$ 278.3	$ 278.0
Other comprehensive income (loss):
Pension and other postretirement adjustments, net of tax	(0.9)	0.6	(0.5)	1.2
Cumulative translation adjustment	2.3	(81.9)	38.9	(101.4)
Other comprehensive income (loss)	1.4	(81.3)	38.4	(100.2)
Comprehensive income	139.9	56.8	316.7	177.8
Comprehensive loss attributable to noncontrolling interest	0.1	0.1	0.1	0.2
Comprehensive income attributable to IDEX	$ 140.0	$ 56.9	$ 316.8	$ 178.0