CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 145,058	$ 147,002
Restricted cash and cash equivalents	2,765	2,765
Accounts and other receivables, net	17,777	15,609
Inventories, net	28,082	25,642
Prepaid expenses and other	3,667	2,630
Total current assets	197,349	193,648
Other assets:
Restricted cash and cash equivalents	25,475	25,475
Note receivable from affiliate	18,100	18,700
Marketable securities	35,106	34,435
Investment in Kronos Worldwide, Inc.	278,892	264,803
Goodwill	27,156	27,156
Other assets, net	2,746	2,753
Total other assets	387,475	373,322
Property and equipment:
Land	5,071	5,071
Buildings	23,161	23,161
Equipment	72,649	70,664
Construction in progress	1,713	2,028
Property and equipment, gross	102,594	100,924
Less accumulated depreciation	72,697	71,742
Net property and equipment	29,897	29,182
Total assets	614,721	596,152
Current liabilities:
Accounts payable	5,126	3,408
Accrued litigation settlement	11,887	11,830
Accrued and other current liabilities	7,182	12,017
Accrued environmental remediation and related costs	2,605	2,643
Payables to affiliates	698	691
Income taxes	8	8
Total current liabilities	27,506	30,597
Noncurrent liabilities:
Long-term debt from affiliate	500	500
Accrued environmental remediation and related costs	90,299	90,297
Long-term litigation settlement	38,702	38,519
Deferred income taxes	47,493	44,056
Accrued pension costs	3,620	3,722
Other	3,423	3,490
Total noncurrent liabilities	184,037	180,584
NL stockholders' equity:
Common stock	6,100	6,100
Additional paid-in capital	300,210	299,775
Retained earnings	312,492	297,351
Accumulated other comprehensive loss	(238,371)	(240,756)
Total NL stockholders' equity	380,431	362,470
Noncontrolling interest in subsidiary	22,747	22,501
Total equity	403,178	384,971
Total liabilities and equity	614,721	596,152
Commitments and contingencies (Notes 12 and 14)