Quarterly Results of Operations (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Quarterly Results of Operations

	Quarter ended
	March 31		June 30			Sept. 30		Dec. 31
	(In millions, except per share data)
Year ended December 31, 2014
Net sales	$	25.8	$	26.8		$	26.5	$	24.7
Gross margin		7.7		8.6			8.2		7.7
Net income		4.1		5.8			14.1		5.6
Net income attributable to NL stockholders		3.7		5.5			13.9		5.4
Income per common share attributable to    NL stockholders	$	.08	$	.11		$	.29	$	.11
Year ended December 31, 2015
Net sales	$	27.9	$	28.9		$	26.5	$	25.7
Gross margin		8.6		9.1			8.1		7.6
Net income (loss)		10.3		(28.8	)		1.2		(5.4	)
Net income (loss) attributable to NL stockholders		10.0		(29.2	)		.9		(5.6	)
Income (loss) per common share attributable to    NL stockholders	$	.21	$	(.60	)	$	.02	$	(.11	)