Significant Accounting Policies (Details) - USD ($) $ in Millions		6 Months Ended			12 Months Ended
		Dec. 31, 2019	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2018	Jul. 02, 2019	Jul. 01, 2019
Capital Expenditures Incurred but Not yet Paid			$ (8)	$ (7)	$ (2)	$ (5)
Depreciation		$ 90		40	131	86
Accelerated Depreciation					2	4
Pension liability fair value adjustment								$ (44)
Goodwill		164	164		164		$ 178
Unrealized gains (losses) on pension and OPEB plan liabilities		5		0	4	(13)
Foreign Currency Transaction Gain (Loss), before Tax		5		(8)		30
Interest-bearing time deposits and other cash equivalents		74	74		20
Unamortized Debt Issuance Expense					1
Asset impairments (see Note 8)		0	0	0	16	28
Research and Development Expense		20		21	38	43
Business realignment costs	[1]	22		14	$ 69	27
Concentration Risk, Percentage					9.00%
Other intangible assets, net		1,125	1,125		$ 1,079
Establishment of Successor other intangible assets							1,219	1,219
Contract with Customer, Asset, Sale		6			5
Capitalized Turnaround Costs Noncurrent		2	2		7
Restricted Cash and Cash Equivalents		4	4		4
Allowance for Doubtful Accounts, Premiums and Other Receivables		3	3		3
Fresh Start Adjustments [Member]
Pension liability fair value adjustment								44
Continuing Operations
Pension liability fair value adjustment								(39)
Goodwill		$ 164	$ 164	$ 83	164	$ 84	$ 164	0
Establishment of Successor other intangible assets								1,155
Continuing Operations | Fresh Start Adjustments [Member]
Pension liability fair value adjustment								$ (39)
Continuing Operations | Epoxy
Goodwill					1
Continuing Operations | Forest Products
Goodwill					127
Continuing Operations | Versatics
Goodwill					$ 36
Minimum [Member]
Property, Plant and Equipment, Useful Life					1 year
Finite-Lived Intangible Asset, Useful Life					15 years
Minimum [Member] | Building [Member]
Property, Plant and Equipment, Useful Life					9 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life					1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life					5 years
Finite-Lived Intangible Asset, Useful Life					25 years
Maximum [Member] | Building [Member]
Property, Plant and Equipment, Useful Life					39 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life					20 years

[1] Business realignment costs for the Successor and Predecessor periods below included: SuccessorPredecessorYear Ended December 31, 2020July 2, 2019 through
December 31, 2019January 1, 2019 through
July 1, 2019Year Ended December 31, 2018Severance costs$16 $9 $8 $9 In-process facility rationalizations11 5 3 11 Contractual costs from exited business8 — — — Business services implementation22 — — — Legacy environmental reserves9 7 1 5 Other3 1 2 2  (a)     The Company had $8 of severance liabilities accrued within “Other current liabilities” on the Consolidated Balance Sheets at both December 31, 2020 and 2019. The Company expects the amounts associated with these severance liabilities to be paid over the next 12 months.