Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		3 Months Ended		6 Months Ended	9 Months Ended
	Jul. 01, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2020
Net Income (Loss) Attributable to Parent	$ 3,054	$ (102)	$ (43)	$ 2,895	$ (203)
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	0	7	(16)	(8)	(29)
Unrealized loss on cash flow hedge	0	(1)	0	0	(19)
Other comprehensive income (loss)	0	6	(16)	(8)	(48)
Comprehensive (loss) income	3,054	(96)	(59)	2,887	(251)
Comprehensive income attributable to noncontrolling interest	0	0	0	(1)	0
Comprehensive (loss) income attributable to Hexion Inc.	$ 3,054	$ (96)	$ (59)	$ 2,886	$ (251)