Contingencies - Additional Information (Detail) - Contingencies Disclosed in Contingencies Note $ in Millions |
Mar. 31, 2016
USD ($)
|
|---|---|
| Loss Contingencies [Line Items] | |
| Accrual for disclosed loss contingencies, current, ending balance | $ 520 |
| Accrual for disclosed loss contingencies, noncurrent, ending balance | 10 |
| Amount not accrued for estimated maximum losses for disclosed loss contingencies | $ 1,600 |