XML 60 R49.htm IDEA: XBRL DOCUMENT v3.20.2
Long-Term Debt - Valhi Contran Credit Facility - Additional Information (Detail)
$ in Millions
9 Months Ended
Sep. 30, 2020
USD ($)
Debt Instrument [Line Items]  
Borrowings of credit facility $ 0.0
Repaid credit facility $ 11.8
VALHI, INC. | Contran Credit Facility  
Debt Instrument [Line Items]  
Debt instrument, Interest rate at period end 4.60%
Debt instrument, Interest rate during period 4.25%
Amount available for borrowing $ 58.8