Term Loan	9 Months Ended
Sep. 30, 2017
Debt Disclosure [Abstract]
Term Loan	Term Loan On August 10, 2016, an indirect subsidiary of the Company, Westlake International Holdings II C.V., a limited partnership organized under the laws of the Netherlands (the "CV Borrower"), entered into a credit agreement with Bank of America, N.A., as agent and lender, providing the CV Borrower with a $150,000 term loan facility. The term loan facility had a maturity date of March 31, 2017. The term loan was fully repaid in January 2017. The loans thereunder bore interest at a floating interest rate equal to LIBOR plus 2% per annum, payable in arrears on the last day of each three-month period following the date of funding and at maturity.

Term Loan

9 Months Ended

Sep. 30, 2017

On August 10, 2016, an indirect subsidiary of the Company, Westlake International Holdings II C.V., a limited partnership organized under the laws of the Netherlands (the "CV Borrower"), entered into a credit agreement with Bank of America, N.A., as agent and lender, providing the CV Borrower with a $150,000 term loan facility. The term loan facility had a maturity date of March 31, 2017. The term loan was fully repaid in January 2017. The loans thereunder bore interest at a floating interest rate equal to LIBOR plus 2% per annum, payable in arrears on the last day of each three-month period following the date of funding and at maturity.