Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Millions			9 Months Ended
	Feb. 01, 2022	Oct. 01, 2021	Sep. 30, 2022
Business Acquisition [Line Items]
Goodwill acquired during the period			$ 119
Measurement period adjustments			$ 25
Hexion
Business Acquisition [Line Items]
Cash	$ 42
Accounts receivable	299
Inventories	346
Prepaid expenses and other current assets	24
Property, plant and equipment	660
Operating lease right-of-use assets	59
Intangible assets	145
Other assets	104
Total assets acquired	1,679
Accounts payable	189
Accrued and other liabilities	84
Deferred income taxes	95
Pensions and other post-retirement benefits	163
Operating lease liabilities	48
Other liabilities	19
Total liabilities assumed	598
Total identifiable net assets acquired	1,081
Noncontrolling interest	(2)
Goodwill acquired during the period	128
Total Westlake Corporation purchase consideration	1,207
Measurement period adjustments	$ 9
Boral Target Companies
Business Acquisition [Line Items]
Cash		$ 5
Accounts receivable		119
Inventories		156
Prepaid expenses and other current assets		3
Property, plant and equipment		482
Operating lease right-of-use assets		87
Intangible assets		952
Other assets		18
Total assets acquired		1,822
Accounts payable		46
Accrued and other liabilities		105
Deferred income taxes		243
Operating lease liabilities		73
Other liabilities		2
Total liabilities assumed		469
Total identifiable net assets acquired		1,353
Goodwill acquired during the period		787
Total Westlake Corporation purchase consideration		2,140
Measurement period adjustments		$ 16