Commitments and Contingencies Fiscal Year Maturity Schedule (Details) $ in Millions	Dec. 31, 2015 USD ($)
Loans and Mortgage-Related Securities [Abstract]
2016	$ 58,715
2017	0
2018	0
2019	0
2020	0
Thereafter	0
Total	58,715
Operating Leases [Abstract]
2016	44
2017	46
2018	32
2019	49
2020	53
Thereafter	718
Total	942
Other [Abstract]
2016	59
2017	15
2018	11
2019	5
2020	4
Thereafter	0
Total	94
Mortgage commitment derivatives [Member]
Loans and Mortgage-Related Securities [Abstract]
Total	$ 58,500