CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 90,063	$ 93,162
Restricted cash and cash equivalents	3,223	3,791
Accounts and other receivables, net	12,373	10,586
Inventories, net	15,317	14,974
Prepaid expenses and other	904	986
Total current assets	121,880	123,499
Other assets:
Notes receivable from affiliate	39,500	27,400
Marketable securities	42,831	49,731
Investment in Kronos Worldwide, Inc.	188,969	120,346
Goodwill	27,156	27,156
Other assets, net	3,472	3,276
Total other assets	301,928	227,909
Property and equipment:
Land	5,146	5,146
Buildings	22,827	22,811
Equipment	66,244	66,112
Construction in progress	1,538	1,098
Property and equipment, gross	95,755	95,167
Less accumulated depreciation	62,466	61,583
Net property and equipment	33,289	33,584
Total assets	457,097	384,992
Current liabilities:
Accounts payable	4,638	5,026
Accrued and other current liabilities	8,390	10,624
Accrued environmental remediation and related costs	13,101	13,350
Payable to affiliates	717	1,717
Income taxes	28	26
Total current liabilities	26,874	30,743
Noncurrent liabilities:
Long-term debt from affiliate	500	500
Accrued pension costs	12,563	12,874
Accrued postretirement benefits (OPEB) costs	2,153	2,310
Accrued environmental remediation and related costs	106,058	103,308
Deferred income taxes	49,464	27,445
Other	13,515	13,542
Total noncurrent liabilities	184,253	159,979
NL stockholders' equity:
Common stock	6,089	6,088
Additional paid-in capital	300,869	300,674
Retained earnings	153,521	104,004
Accumulated other comprehensive loss	(231,549)	(232,846)
Total NL stockholders' equity	228,930	177,920
Noncontrolling interest in subsidiary	17,040	16,350
Total equity	245,970	194,270
Total liabilities and equity	457,097	384,992
Commitments and contingencies (Note 13)