Securities - OTTI Significant Assumptions (Details) - Non-agency residential	Jun. 30, 2015
Weighted Average
Significant Assumptions:
Annual prepayment speed	12.00%
Loss severity	38.90%
Life default rate	34.60%
Weighted Average \| Prime
Significant Assumptions:
Loss severity	35.60%
Life default rate	21.50%
Weighted Average \| Alt-A Loan
Significant Assumptions:
Loss severity	37.40%
Life default rate	36.90%
Weighted Average \| Subprime
Significant Assumptions:
Loss severity	50.40%
Life default rate	38.20%
10th Percentile
Significant Assumptions:
Annual prepayment speed	3.70%
Loss severity	13.20%
Life default rate	1.30%
90th Percentile
Significant Assumptions:
Annual prepayment speed	24.20%
Loss severity	48.00%
Life default rate	97.50%