Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Investments	$ 258	$ 251
Investments in equity affiliates
Debt and Equity Securities, FV-NI [Line Items]
Investments	129	132
Marketable equity securities (See Note 10) | Trading Securities
Debt and Equity Securities, FV-NI [Line Items]
Investments	80	69
Other
Debt and Equity Securities, FV-NI [Line Items]
Investments	$ 49	$ 50