Commitments, Guarantees and Contingencies Aggregate Minimum Rentals (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
2017		$ 64
2018		57
2019		44
2020		35
2021		23
Thereafter		72
Total	[1]	295
Operating lease expense		$ 59	$ 67	$ 85

[1] Minimum payments have not been reduced by minimum sublease rentals due in the future under noncancelable subleases.