CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net sales	$ 25,781	$ 21,453
Cost of sales	18,032	15,433
Gross margin	7,749	6,020
Selling, general and administrative expense	4,461	4,586
Other operating income (expense):
Insurance recoveries	787	630
Other income	131
Corporate expense and other, net	(4,270)	(4,917)
Loss from operations	(64)	(2,853)
Equity in earnings (loss) of Kronos Worldwide, Inc.	4,343	(12,487)
Other income (expense):
Interest and dividends	725	743
Interest expense		(59)
Income (loss) before income taxes	5,004	(14,656)
Income tax expense (benefit)	970	(12,658)
Net income (loss)	4,034	(1,998)
Noncontrolling interest in net income of subsidiary	279	120
Net income (loss) attributable to NL stockholders	$ 3,755	$ (2,118)
Amounts attributable to NL stockholders:
Basic and diluted net income (loss) per share	$ 0.08	$ (0.04)
Cash dividend per share		$ 0.125
Weighted average shares used in the calculation of net income (loss) per share	48,674	48,669