Derivatives and Hedging - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| Derivative [Line Items] | |||
| Derivative maximum risk of loss for credit protection | $ 17 | $ 17 | |
| Forward Foreign Currency Exchange Contracts [Member] | |||
| Derivative [Line Items] | |||
| Notional value | 1,500 | 1,500 | |
| Fair value of the outstanding forward foreign currency exchange contracts | 35 | ||
| Other General and Administration Expense [Member] | |||
| Derivative [Line Items] | |||
| Foreign currency translation gains (losses) | 30 | ||
| Total Return Swaps [Member] | |||
| Derivative [Line Items] | |||
| Notional value | $ 546 | $ 587 | |
| Total Return Swaps [Member] | Nonoperating Income (Expense) [Member] | |||
| Derivative [Line Items] | |||
| Amount of gains (losses) recognized in income on derivative instruments | $ (35) | ||