Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 7,480	$ 11,652
Restricted cash and cash equivalents	3,502	3,337
Accounts and other receivables, net	18,209	15,160
Inventories, net	19,210	19,578
Prepaid expenses and other	1,713	1,364
Deferred income taxes	7,213	7,213
Total current assets	57,327	58,304
Other assets:
Marketable securities	195,907	311,419
Investment in Kronos Worldwide, Inc.	320,689	281,257
Goodwill	47,593	47,553
Assets held for sale	6,649	6,649
Other assets, net	3,547	4,258
Total other assets	574,385	651,136
Property and equipment:
Land	11,617	11,639
Buildings	27,278	27,301
Equipment	128,238	129,685
Construction in progress	2,215	1,477
Property and equipment, gross	169,348	170,102
Less accumulated depreciation	117,522	118,300
Net property and equipment	51,826	51,802
Total assets	683,538	761,242
Current liabilities:
Current maturities of long-term debt	6,100	10,000
Accounts payable	7,398	8,184
Accrued and other current liabilities	14,042	13,994
Accrued environmental remediation and related costs	9,160	7,301
Income taxes	277	1,327
Total current liabilities	36,977	40,806
Noncurrent liabilities:
Long-term debt	21,926	27,285
Accrued pension costs	14,526	16,743
Accrued postretirement benefit (OPEB) costs	4,198	4,373
Accrued environmental remediation and related costs	44,519	34,336
Deferred income taxes	163,996	192,492
Other	18,449	19,215
Total noncurrent liabilities	267,614	294,444
NL Stockholders' equity:
Common stock	6,083	6,082
Additional paid-in capital	300,246	300,067
Retained earnings	148,411	113,555
Accumulated other comprehensive loss	(86,892)	(4,724)
Total NL stockholders' equity	367,848	414,980
Noncontrolling interest in subsidiary	11,099	11,012
Total equity	378,947	425,992
Total liabilities and equity	683,538	761,242
Commitments and contingencies (Notes 11 and 12)