Related Party Transactions Level 4 (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Apollo [Member]
Related Party Transaction [Line Items]
Annual management consulting fee	$ 3	$ 3	$ 3
Annual management consulting fee percentage	2.00%	2.00%	2.00%
Management Consulting Fees	$ 3	$ 3	$ 3
Momentive Performance Materials Inc. [Member]
Related Party Transaction [Line Items]
Shared Service Cost Allocation Percentage - MSC	57.00%	56.00%	56.00%
Shared Service Cost Allocation Percentage - MPM	43.00%	44.00%	44.00%
Due from Related Parties	$ 2	$ 3
Related Party Transaction, Purchases from Related Party	32	24	$ 27
Accounts Payable, Related Parties	3	2
Revenues from distribution agreement	1	1	1
Related Party Transaction, Other Revenues from Transactions with Related Party	0
Apollo Affiliates and Other Related Parties [Member]
Related Party Transaction [Line Items]
Net Sales to Related Parties	0	0	0
Accounts Receivable, Related Parties	1	1
Purchases From Related Parties	1	0	1
Subsidiary of Common Parent [Member]
Related Party Transaction [Line Items]
Shared Services Costs Incurred by MPM	21	38	50
Other joint ventures unconsolidated [Member]
Related Party Transaction [Line Items]
sales to joint venture	9	17	43
due to joint ventures	1	1
Due to Related Parties	1	1
Accounts Receivable, Related Parties	2	6
Purchases from JV	6	14	17
Co-venturer [Member]
Related Party Transaction [Line Items]
Accounts Receivable, Related Parties, Current	7	6
Momentive Specialty Chemicals Inc. [Member]
Related Party Transaction [Line Items]
Shared Services Net Billings - Hexion to MPM	0	0	0
Shared Services Costs Incurred by Hexion	$ 28	$ 48	$ 63

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