Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of account and note receivables due from other than related parties.

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Commitments and Contingencies - Additional Information (Details) R$ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)	Mar. 31, 2019 BRL (R$)	Mar. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Discount rate, percent	3.125%	3.125%
Tax credits generated from purchase of certain goods	$ 2.5	R$ 9.6
Shell Chemicals
Loss Contingencies [Line Items]
Receivables			$ 0.2
Minimum
Loss Contingencies [Line Items]
Term of contract	1 year