Schedule II - Valuation and Qualifying Accounts (Detail) - Valuation Allowance of Deferred Tax Assets [Member] - USD ($) $ in Millions |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
Valuation and Qualifying Accounts Disclosure [Line Items] | |||
Balance at Beginning of Year | $ 226 | $ 200 | $ 153 |
Addition Charged to Expenses | 40 | 23 | 52 |
Additions (Deductions) | 3 | (5) | |
Balance at End of Year | $ 266 | $ 226 | $ 200 |