Income Taxes (Tables)

9 Months Ended

Sep. 30, 2016

Income Tax Disclosure [Abstract]

Component of Income Taxes

	Three months ended						Nine months ended
	September 30,						September 30,
	2015			2016			2015			2016
	(In millions)
Expected tax expense (benefit), at U.S. federal    statutory income tax rate of 35%	$	(.8	)	$	2.5		$	(15.0	)	$	2.0
Rate differences on equity in earnings (losses) of    Kronos		(2.7	)		(3.0	)		(7.4	)		(2.8	)
Adjustment to the reserve for uncertain tax    positions, net		—			—			(3.0	)		—
Nontaxable income		(.1	)		(.2	)		(.3	)		(.4	)
U.S. state income taxes and other, net		.1			.1			.2			.1
Income tax expense (benefit)	$	(3.5	)	$	(.6	)	$	(25.5	)	$	(1.1	)
Comprehensive provision for income taxes    (benefit) allocable to:
Net income (loss)	$	(3.5	)	$	(.6	)	$	(25.5	)	$	(1.1	)
Other comprehensive income (loss):
Marketable securities		(18.6	)		3.7			(22.4	)		4.9
Currency translation		(2.0	)		1.0			(8.3	)		2.0
Interest rate swap		(.4	)		.1			(.4	)		(.3	)
Pension plans		.5			.4			1.5			1.3
OPEB plans		—			(.1	)		(.2	)		(.2	)
Total	$	(24.0	)	$	4.5		$	(55.3	)	$	6.6