Investment Securities - Schedule of Credit Losses Related to Debt Securities Recognized in Earnings (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ||||
Credit loss component, beginning of period | $ 192 | $ 165 | $ 175 | $ 160 |
Additions: | ||||
Initial credit impairment | 2 | 1 | 7 | 2 |
Subsequent credit impairment | 3 | 2 | 15 | 6 |
Total additions | 5 | 3 | 22 | 8 |
Reductions due to payoffs, disposals, transfers and other | (1) | (2) | (1) | (2) |
Credit loss component, end of period | $ 196 | $ 166 | $ 196 | $ 166 |