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Long-Term Debt - Additional Information (Detail) - NLKW Holding, LLC - USD ($) shares in Millions | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Nov. 30, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | Nov. 14, 2016
Kronos |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Asset contribution, equity security shares | 35.2 |  |  |
Back-To-Back Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing under credit facility | $ 50,000,000 |  |  |
Percentage of membership interest in subsidiary | 100.00% |  |  |
Valhi | Valhi Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing under credit facility | $ 50,000,000 |  |  | $ 50,000,000
Variable rate basis spread above reference rate | 1.875% |  |  |
Line of credit facility frequency of payment of interest |  | quarterly |  |
Line of credit facility expiration date |  | Dec. 31, 2023 |  |
Maximum principle outstanding, percentage of collateral value | 50.00% |  |  |
Debt instrument collateral |  | 100% of the membership interest in NLKW held by us |  |
Percentage of membership interest in subsidiary | 100.00% |  |  |
Outstanding borrowing |  | $ 500,000 | $ 500,000 |
Debt instrument average interest rate |  | 6.63% |  |
Debt instrument average interest rate, during period |  | 7.16% |  |
Valhi | Stock Repurchase Rights [Member] | Valhi Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Variable rate basis spread above reference rate | 2.75% |  |  |
Stock repurchase, maximum debt percentage | 50.00% |  |  |
Debt instrument maturity period |  | 5 years |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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