CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 145,273	$ 137,039
Restricted cash and cash equivalents	2,734	2,695
Accounts and other receivables, net	16,672	11,142
Receivables from affiliates		313
Inventories, net	19,948	18,337
Prepaid expenses and other	1,998	1,638
Total current assets	186,625	171,164
Other assets:
Restricted cash and cash equivalents	25,502	25,538
Note receivable from affiliate	26,000	29,500
Marketable securities	29,141	18,206
Investment in Kronos Worldwide, Inc.	246,853	242,374
Goodwill	27,156	27,156
Other assets, net	5,361	5,262
Total other assets	360,013	348,036
Property and equipment:
Land	4,940	4,940
Buildings	23,146	23,146
Equipment	69,317	68,227
Construction in progress	1,246	1,010
Property and equipment, gross	98,649	97,323
Less accumulated depreciation	69,940	68,373
Net property and equipment	28,709	28,950
Total assets	575,347	548,150
Current liabilities:
Accounts payable	3,754	2,647
Accrued litigation settlement	11,943	11,830
Accrued and other current liabilities	8,845	10,253
Accrued environmental remediation and related costs	2,257	2,027
Payables to affiliates	739	725
Income taxes		25
Total current liabilities	27,538	27,507
Noncurrent liabilities:
Long-term debt from affiliate	500	500
Accrued environmental remediation and related costs	90,654	91,389
Long-term litigation settlement	49,873	49,403
Deferred income taxes	39,045	33,830
Accrued pension costs	5,525	6,392
Other	3,637	3,780
Total noncurrent liabilities	189,234	185,294
NL stockholders' equity:
Common stock	6,100	6,098
Additional paid-in capital	300,309	299,093
Retained earnings	277,974	257,875
Accumulated other comprehensive loss	(248,082)	(251,189)
Total NL stockholders' equity	336,301	311,877
Noncontrolling interest in subsidiary	22,274	23,472
Total equity	358,575	335,349
Total liabilities and equity	575,347	548,150
Commitments and contingencies (Note 14)