CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income (loss)	$ 302.6	$ (3.0)	$ (171.1)
Other comprehensive income (loss), net of tax:
Currency translation	47.9	(14.5)	(77.0)
Interest rate swap	1.5	0.2	(1.8)
Marketable securities	5.0	4.0	(7.5)
Total other comprehensive income (loss), net	64.6	(30.9)	(74.4)
Comprehensive income (loss)	367.2	(33.9)	(245.5)
Comprehensive income (loss) attributable to noncontrolling interest	116.8	(6.9)	(63.5)
Comprehensive income (loss) attributable to Valhi stockholders	250.4	(40.8)	(182.0)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Pension and other postretirement benefit plan	11.0	(19.7)	12.6
OPEB
Other comprehensive income (loss), net of tax:
Pension and other postretirement benefit plan	$ (0.8)	$ (0.9)	$ (0.7)