Organization and Basis of Presentation	3 Months Ended
Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Basis of Presentation	Note 1—Organization and basis of presentation: Organization— We are majority owned by a wholly-owned subsidiary of Contran Corporation (“Contran”), which owns approximately 93% of our outstanding common stock at March 31, 2018. All of Contran's outstanding voting stock is held by a family trust established for the benefit of Lisa K. Simmons and Serena Simmons Connelly and their children, for which Ms. Simmons and Ms. Connelly are co-trustees, or is held directly by Ms. Simmons and Ms. Connelly or entities related to them. Consequently, Ms. Simmons and Ms. Connelly may be deemed to control Contran and us. Basis of Presentation—Consolidated in this Quarterly Report are the results of our majority-owned and wholly-owned subsidiaries, including NL Industries, Inc., Kronos Worldwide, Inc., CompX International Inc., Tremont LLC, Basic Management, Inc. (“BMI”) and The LandWell Company (“LandWell”). Kronos (NYSE: KRO), NL (NYSE: NL), and CompX (NYSE MKT: CIX) each file periodic reports with the Securities and Exchange Commission (“SEC”). In January 2018, we sold Waste Control Specialists LLC (“WCS”). See Note 3. The unaudited Condensed Consolidated Financial Statements contained in this Quarterly Report have been prepared on the same basis as the audited Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2017 that we filed with the SEC on March 15, 2018 (the “2017 Annual Report”). In our opinion, we have made all necessary adjustments (which include only normal recurring adjustments, other than the gain on the sale of WCS recognized in the first quarter of 2018 as discussed in Note 3), in order to state fairly, in all material respects, our consolidated financial position, results of operations and cash flows as of the dates and for the periods presented. We have condensed the Consolidated Balance Sheet at December 31, 2017 contained in this Quarterly Report as compared to our audited Consolidated Financial Statements at that date, and we have omitted certain information and footnote disclosures (including those related to the Consolidated Balance Sheet at December 31, 2017) normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Our results of operations for the interim period ended March 31, 2018 may not be indicative of our operating results for the full year. The Condensed Consolidated Financial Statements contained in this Quarterly Report should be read in conjunction with our 2017 Consolidated Financial Statements contained in our 2017 Annual Report. Unless otherwise indicated, references in this report to “we,” “us” or “our” refer to Valhi, Inc. and its subsidiaries (NYSE: VHI), taken as a whole.

Note 1—Organization and basis of presentation:

Organization— We are majority owned by a wholly-owned subsidiary of Contran Corporation (“Contran”), which owns approximately 93% of our outstanding common stock at March 31, 2018. All of Contran's outstanding voting stock is held by a family trust established for the benefit of Lisa K. Simmons and Serena Simmons Connelly and their children, for which Ms. Simmons and Ms. Connelly are co-trustees, or is held directly by Ms. Simmons and Ms. Connelly or entities related to them. Consequently, Ms. Simmons and Ms. Connelly may be deemed to control Contran and us.

Basis of Presentation—Consolidated in this Quarterly Report are the results of our majority-owned and wholly-owned subsidiaries, including NL Industries, Inc., Kronos Worldwide, Inc., CompX International Inc., Tremont LLC, Basic Management, Inc. (“BMI”) and The LandWell Company (“LandWell”). Kronos (NYSE: KRO), NL (NYSE: NL), and CompX (NYSE MKT: CIX) each file periodic reports with the Securities and Exchange Commission (“SEC”). In January 2018, we sold Waste Control Specialists LLC (“WCS”). See Note 3.

The unaudited Condensed Consolidated Financial Statements contained in this Quarterly Report have been prepared on the same basis as the audited Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2017 that we filed with the SEC on March 15, 2018 (the “2017 Annual Report”). In our opinion, we have made all necessary adjustments (which include only normal recurring adjustments, other than the gain on the sale of WCS recognized in the first quarter of 2018 as discussed in Note 3), in order to state fairly, in all material respects, our consolidated financial position, results of operations and cash flows as of the dates and for the periods presented. We have condensed the Consolidated Balance Sheet at December 31, 2017 contained in this Quarterly Report as compared to our audited Consolidated Financial Statements at that date, and we have omitted certain information and footnote disclosures (including those related to the Consolidated Balance Sheet at December 31, 2017) normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Our results of operations for the interim period ended March 31, 2018 may not be indicative of our operating results for the full year. The Condensed Consolidated Financial Statements contained in this Quarterly Report should be read in conjunction with our 2017 Consolidated Financial Statements contained in our 2017 Annual Report.

Unless otherwise indicated, references in this report to “we,” “us” or “our” refer to Valhi, Inc. and its subsidiaries (NYSE: VHI), taken as a whole.