Guarantor Non-Guarantor Subsidiary Financial Information (Details) - Consolidating Statement of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Interest Paid, Capitalized, Investing Activities		$ 1
Cash flows (used in) provided by operating activities	$ (49)	(205)
Cash flows provided by (used in) investing activities
Capital expenditures	(62)	(86)
Proceeds from disposition, net	49
Proceeds from sale of assets, net	1	5
Return of capital from subsidiary from sales of accounts receivable	0	0
Net cash (used in) provided by investing activities	(12)	(82)
Cash flows provided by (used in) financing activities
Net short-term debt borrowings	6	15
Borrowings of long-term debt	425	1,291
Repayments of long-term debt	(343)	(1,079)
Net intercompany loan borrowings (repayments)	0	0
Long-term debt and credit facility financing fees paid	(1)	(25)
Dividends		0
Return of capital to parent from sales of accounts receivable	0	0
Net cash provided by financing activities	87	202
Effect of exchange rates on cash and cash equivalents	(4)	7
Change in cash and cash equivalents	22	(78)
Cash and cash equivalents at beginning of period	115	196
Cash and cash equivalents at end of period	137	118
Hexion Inc. [Member]
Interest Paid, Capitalized, Investing Activities		0
Cash flows (used in) provided by operating activities	(303)	(245)
Cash flows provided by (used in) investing activities
Capital expenditures	(20)	(33)
Proceeds from disposition, net	24
Proceeds from sale of assets, net	0	5
Return of capital from subsidiary from sales of accounts receivable	243	117
Net cash (used in) provided by investing activities	247	89
Cash flows provided by (used in) financing activities
Net short-term debt borrowings	0	4
Borrowings of long-term debt	221	1,007
Repayments of long-term debt	(197)	(850)
Net intercompany loan borrowings (repayments)	53	(7)
Long-term debt and credit facility financing fees paid	0	(20)
Dividends		0
Return of capital to parent from sales of accounts receivable	0	0
Net cash provided by financing activities	77	134
Effect of exchange rates on cash and cash equivalents	0	0
Change in cash and cash equivalents	21	(22)
Cash and cash equivalents at beginning of period	13	28
Cash and cash equivalents at end of period	34	6
Combined Subsidiary Guarantors [Member]
Interest Paid, Capitalized, Investing Activities		0
Cash flows (used in) provided by operating activities	1	0
Cash flows provided by (used in) investing activities
Capital expenditures	0	0
Proceeds from disposition, net	0
Proceeds from sale of assets, net	0	0
Return of capital from subsidiary from sales of accounts receivable	0	0
Net cash (used in) provided by investing activities	0	0
Cash flows provided by (used in) financing activities
Net short-term debt borrowings	0	0
Borrowings of long-term debt	0	0
Repayments of long-term debt	0	0
Net intercompany loan borrowings (repayments)	0	0
Long-term debt and credit facility financing fees paid	0	0
Dividends		0
Return of capital to parent from sales of accounts receivable	0	0
Net cash provided by financing activities	0	0
Effect of exchange rates on cash and cash equivalents	0	0
Change in cash and cash equivalents	1	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	1	0
Combined Non-Guarantor Subsidiaries [Member]
Interest Paid, Capitalized, Investing Activities		1
Cash flows (used in) provided by operating activities	253	41
Cash flows provided by (used in) investing activities
Capital expenditures	(42)	(53)
Proceeds from disposition, net	25
Proceeds from sale of assets, net	1	0
Return of capital from subsidiary from sales of accounts receivable	0	0
Net cash (used in) provided by investing activities	(16)	(54)
Cash flows provided by (used in) financing activities
Net short-term debt borrowings	6	11
Borrowings of long-term debt	204	284
Repayments of long-term debt	(146)	(229)
Net intercompany loan borrowings (repayments)	(53)	7
Long-term debt and credit facility financing fees paid	(1)	(5)
Dividends		(1)
Return of capital to parent from sales of accounts receivable	(243)	(117)
Net cash provided by financing activities	(233)	(50)
Effect of exchange rates on cash and cash equivalents	(4)	7
Change in cash and cash equivalents	0	(56)
Cash and cash equivalents at beginning of period	102	168
Cash and cash equivalents at end of period	102	112
Consolidation, Eliminations [Member]
Interest Paid, Capitalized, Investing Activities		0
Cash flows (used in) provided by operating activities	0	(1)
Cash flows provided by (used in) investing activities
Capital expenditures	0	0
Proceeds from disposition, net	0
Proceeds from sale of assets, net	0	0
Return of capital from subsidiary from sales of accounts receivable	(243)	(117)
Net cash (used in) provided by investing activities	(243)	(117)
Cash flows provided by (used in) financing activities
Net short-term debt borrowings	0	0
Borrowings of long-term debt	0	0
Repayments of long-term debt	0	0
Net intercompany loan borrowings (repayments)	0	0
Long-term debt and credit facility financing fees paid	0	0
Dividends		1
Return of capital to parent from sales of accounts receivable	243	117
Net cash provided by financing activities	243	118
Effect of exchange rates on cash and cash equivalents	0	0
Change in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0