Related Party Transactions Dow Intercompany Transactions (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Dow [Member]
Related Party Transaction [Line Items]
Purchases from Historical Dow and affiliates	$ 42

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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