Guarantor Non-Guarantor Subsidiary Financial Information Level 4 (Details) - Consolidating Statement of Operations - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net sales	$ 946	$ 870
Cost of sales	789	737
Gross profit	157	133
Selling, general and administrative expense	82	79
Gain on disposition	(44)	0
Asset impairments	25	0
Business realignment costs	9	7
Other operating expense (income), net	9	(6)
Operating income	76	53
Interest expense, net	83	83
Intercompany interest expense (income)	0	0
Loss on extinguishment of debt	0	3
Other non-operating (income) expense, net	(1)	2
Loss before income tax and earnings from unconsolidated entities	(6)	(35)
Income tax expense	8	8
Loss before earnings from unconsolidated entities	(14)	(43)
(Losses) earnings from unconsolidated entities, net of taxes	1	1
Net loss	(13)	(42)
Comprehensive income (loss)	1	(36)
Hexion Inc. [Member]
Net sales	431	378
Cost of sales	357	322
Gross profit	74	56
Selling, general and administrative expense	36	33
Gain on disposition	(24)
Asset impairments	25
Business realignment costs	6	4
Other operating expense (income), net	0	(6)
Operating income	31	25
Interest expense, net	79	80
Intercompany interest expense (income)	(20)	(17)
Loss on extinguishment of debt		3
Other non-operating (income) expense, net	(19)	(8)
Loss before income tax and earnings from unconsolidated entities	(9)	(33)
Income tax expense	(7)	(6)
Loss before earnings from unconsolidated entities	(2)	(27)
(Losses) earnings from unconsolidated entities, net of taxes	(11)	(15)
Net loss	(13)	(42)
Comprehensive income (loss)	1	(36)
Combined Subsidiary Guarantors [Member]
Net sales	0	0
Cost of sales	0	0
Gross profit	0	0
Selling, general and administrative expense	0	0
Gain on disposition	0
Asset impairments	0
Business realignment costs	0	0
Other operating expense (income), net	0	0
Operating income	0	0
Interest expense, net	0	0
Intercompany interest expense (income)	0	0
Loss on extinguishment of debt		0
Other non-operating (income) expense, net	0	0
Loss before income tax and earnings from unconsolidated entities	0	0
Income tax expense	0	0
Loss before earnings from unconsolidated entities	0	0
(Losses) earnings from unconsolidated entities, net of taxes	(3)	(2)
Net loss	(3)	(2)
Comprehensive income (loss)	(2)	(3)
Combined Non-Guarantor Subsidiaries [Member]
Net sales	570	543
Cost of sales	487	466
Gross profit	83	77
Selling, general and administrative expense	46	46
Gain on disposition	(20)
Asset impairments	0
Business realignment costs	3	3
Other operating expense (income), net	9	0
Operating income	45	28
Interest expense, net	4	3
Intercompany interest expense (income)	20	17
Loss on extinguishment of debt		0
Other non-operating (income) expense, net	18	10
Loss before income tax and earnings from unconsolidated entities	3	(2)
Income tax expense	15	14
Loss before earnings from unconsolidated entities	(12)	(16)
(Losses) earnings from unconsolidated entities, net of taxes	1	1
Net loss	(11)	(15)
Comprehensive income (loss)	2	(3)
Consolidation, Eliminations [Member]
Net sales	(55)	(51)
Cost of sales	(55)	(51)
Gross profit	0	0
Selling, general and administrative expense	0	0
Gain on disposition	0
Asset impairments	0
Business realignment costs	0	0
Other operating expense (income), net	0	0
Operating income	0	0
Interest expense, net	0	0
Intercompany interest expense (income)	0	0
Loss on extinguishment of debt		0
Other non-operating (income) expense, net	0	0
Loss before income tax and earnings from unconsolidated entities	0	0
Income tax expense	0	0
Loss before earnings from unconsolidated entities	0	0
(Losses) earnings from unconsolidated entities, net of taxes	14	17
Net loss	14	17
Comprehensive income (loss)	$ 0	$ 6