Intangible Assets - Schedule of Other Intangible Assets (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Finite Lived Intangible Assets [Line Items]
Net Carrying Amount	$ 1,006
Other Intangible Assets [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	1,041	[1]
Accumulated amortization	(35)	[1]
Net Carrying Amount	1,006	[1]
Other Intangible Assets [Member] | Process Technologies [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	498
Accumulated amortization	(9)
Net Carrying Amount	$ 489
Weighted average life	27 years
Other Intangible Assets [Member] | Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 401
Accumulated amortization	(14)
Net Carrying Amount	$ 387
Weighted average life	12 years
Other Intangible Assets [Member] | Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 115
Accumulated amortization	(11)
Net Carrying Amount	$ 104
Weighted average life	10 years
Other Intangible Assets [Member] | Trademarks [Member]
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 27
Accumulated amortization	(1)
Net Carrying Amount	$ 26
Weighted average life	10 years

[1] All other intangible assets at September 30, 2018 resulted from the Combination. Amortization expense was $25 million and $35 million for the three and nine months ended September 30, 2018, respectively, and is anticipated to be $24 million, $84 million, $83 million, $78 million and $72 million for the remainder of 2018, 2019, 2020, 2021 and 2022, respectively.