Related Party Transactions Level 4 (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Apollo [Member]
Related Party Transaction [Line Items]
Annual management consulting fee			$ 3	$ 3
Annual management consulting fee percentage			2.00%	2.00%
Management Consulting Fees			$ 3	$ 3
Momentive Performance Materials Inc. [Member]
Related Party Transaction [Line Items]
Shared Service Cost Allocation Percentage - MSC		52.00%	57.00%	56.00%
Shared Service Cost Allocation Percentage - MPM		48.00%	43.00%	44.00%
Due to Related Parties			$ 3
Related Party Transaction, Purchases from Related Party		$ 10	32	$ 24
Accounts Receivable, Related Parties			2
Revenues from distribution agreement		1	1	1
Related Party Transaction, Other Revenues from Transactions with Related Party			1	1
Apollo Affiliates and Other Related Parties [Member]
Related Party Transaction [Line Items]
Net Sales to Related Parties		1	2	4
Accounts Receivable, Related Parties			1	1
Purchases From Related Parties		0	0	0
Subsidiary of Common Parent [Member]
Related Party Transaction [Line Items]
Shared Services Costs Incurred by MPM		14	21	38
Other joint ventures unconsolidated [Member]
Related Party Transaction [Line Items]
sales to joint venture	$ 2	2	9	17
due to joint ventures	1		1
Due to Related Parties	0
Accounts Receivable, Related Parties	1		2
Purchases from JV	2	2	6	14
Co-venturer [Member]
Related Party Transaction [Line Items]
Accounts Receivable, Related Parties, Current	$ 7
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		$ 15	$ 28	$ 48

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Purchases From Related Parties

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Revenues from distribution agreement

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Shared Service Cost Allocation Percentage - MPM

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Shared Service Cost Allocation Percentage - MSC

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Shared Services Costs Incurred by MPM

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Shared Services Costs Incurred by Hexion

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Shared Services Net Billings - Hexion to MPM

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