CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 111,140	$ 98,316
Restricted cash and cash equivalents	3,445	3,370
Accounts and other receivables, net	29,079	10,670
Inventories, net	16,579	15,382
Receivable from affiliate		1,767
Prepaid expenses and other	938	1,162
Total current assets	161,181	130,667
Other assets:
Notes receivable from affiliate	37,600	38,200
Marketable securities	68,415	88,681
Investment in Kronos Worldwide, Inc.	259,752	229,543
Goodwill	27,156	27,156
Other assets, net	5,027	4,843
Total other assets	397,950	388,423
Property and equipment:
Land	5,141	5,146
Buildings	22,910	23,044
Equipment	68,447	67,926
Construction in progress	1,013	569
Property and equipment, gross	97,511	96,685
Less accumulated depreciation	65,563	64,159
Net property and equipment	31,948	32,526
Total assets	591,079	551,616
Current liabilities:
Accounts payable	3,684	4,116
Accrued and other current liabilities	68,445	9,707
Accrued environmental remediation and related costs	18,253	5,302
Payable to affiliates	461	429
Income taxes	46	30
Total current liabilities	90,889	19,584
Noncurrent liabilities:
Long-term debt from affiliate	500	500
Accrued pension costs	11,490	12,194
Accrued postretirement benefits (OPEB) costs	1,737	1,846
Accrued environmental remediation and related costs	97,208	106,607
Deferred income taxes	39,563	49,315
Other	25,413	8,492
Total noncurrent liabilities	175,911	178,954
NL stockholders' equity:
Common stock	6,090	6,089
Additional paid-in capital	301,139	300,866
Retained earnings	237,807	220,104
Accumulated other comprehensive loss	(239,504)	(191,737)
Total NL stockholders' equity	305,532	335,322
Noncontrolling interest in subsidiary	18,747	17,756
Total equity	324,279	353,078
Total liabilities and equity	591,079	551,616
Commitments and contingencies (Note 14)