CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 101.3	$ 45.6
Other comprehensive income:
Net foreign currency translation adjustment	26.5	19.2
Net change in postretirement benefit plans, net of tax impacts of $0.4 and $0.5, respectively	1.1	1.1
Other comprehensive income	27.6	20.3
Comprehensive income	128.9	65.9
Less: Comprehensive income (loss) attributable to noncontrolling interests	0.1	(0.4)
Comprehensive income attributable to ITT Inc.	128.8	66.3
Reclassification adjustments (see Note 15):
Amortization of prior service benefit, net of tax expense of $(0.2) and $(0.5), respectively	(0.9)	(0.7)
Amortization of net actuarial loss, net of tax benefits of $0.6 and $1.0, respectively	2.0	1.8
Net change in postretirement benefit plans, net of tax impacts of $0.4 and $0.5, respectively	$ 1.1	$ 1.1