Related party transactions (Tables)

12 Months Ended

Dec. 31, 2023

Related Party Transactions [Abstract]

Receivables from and Payables to Affiliates

	December 31,
	2022		2023
	(In millions)
Current receivables from affiliates:
LPC	$	—	$	16.9
Contran - trade items		.2		.2
Other		2.7		.4
Total	$	2.9	$	17.5
Current payables to affiliates:
LPC	$	17.1	$	19.9
Contran - income taxes		5.8		10.2
Total	$	22.9	$	30.1
Noncurrent payable to affiliates:
Contran - income taxes	$	33.4	$	18.5
Payables to affiliate included in long-term debt:
Valhi - Contran credit facility	$	121.4	$	93.4