Fair Value Measurements (Assets Measured on a Nonrecurring Basis, Level 3 Quantitative Information) (Details) - Nonrecurring - USD ($)
$ in Millions |
9 Months Ended |
12 Months Ended |
Sep. 30, 2016 |
Dec. 31, 2015 |
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Repossessed assets |
$ 15
|
$ 17
|
| Residential first mortgage loans |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
22
|
40
|
| Commercial and industrial |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
1
|
2
|
| Level 3 |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Repossessed assets |
15
|
17
|
| Level 3 | Residential first mortgage loans |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
22
|
40
|
| Level 3 | Residential first mortgage loans | Fair value of underlying collateral |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
$ 22
|
$ 40
|
| Level 3 | Residential first mortgage loans | Fair value of underlying collateral | Lower range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
23.00%
|
35.00%
|
| Level 3 | Residential first mortgage loans | Fair value of underlying collateral | Upper range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
28.00%
|
45.00%
|
| Level 3 | Residential first mortgage loans | Fair value of underlying collateral | Weighted Average |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
25.60%
|
35.20%
|
| Level 3 | Commercial and industrial |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
$ 1
|
$ 2
|
| Level 3 | Commercial and industrial | Fair value of underlying collateral |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
$ 1
|
|
| Level 3 | Commercial and industrial | Fair value of underlying collateral | Lower range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
50.00%
|
|
| Level 3 | Commercial and industrial | Fair value of underlying collateral | Upper range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
55.00%
|
|
| Level 3 | Commercial and industrial | Fair value of underlying collateral | Weighted Average |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
53.40%
|
|
| Level 3 | Commercial real estate | Fair value of underlying collateral |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Impaired loans held-for-investment |
|
$ 2
|
| Level 3 | Commercial real estate | Fair value of underlying collateral | Lower range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
|
45.00%
|
| Level 3 | Commercial real estate | Fair value of underlying collateral | Upper range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
|
55.00%
|
| Level 3 | Commercial real estate | Fair value of underlying collateral | Weighted Average |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
|
50.10%
|
| Level 3 | Repossessed assets | Fair value of underlying collateral |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Repossessed assets |
$ 15
|
|
| Level 3 | Repossessed assets | Fair value of underlying collateral | Lower range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
35.00%
|
16.00%
|
| Level 3 | Repossessed assets | Fair value of underlying collateral | Upper range |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
98.00%
|
100.00%
|
| Level 3 | Repossessed assets | Fair value of underlying collateral | Weighted Average |
|
|
| Fair Value Inputs, Assets, Quantitative Information [Line Items] |
|
|
| Loss severity (as a percent) |
61.70%
|
48.70%
|