Derivative Financial Instruments - External Credit Ratings of Underlyings or Referenced Assets (Details) - USD ($) $ in Millions	Aug. 31, 2017	Nov. 30, 2016
Index credit default swaps
Derivative [Line Items]
Total Notional	$ 1,361	$ 54
Single name credit default swaps
Derivative [Line Items]
Total Notional	331	383
Investment Grade | Index credit default swaps
Derivative [Line Items]
Total Notional	1,103	54
Investment Grade | Single name credit default swaps
Derivative [Line Items]
Total Notional	139	122
Non-investment Grade | Index credit default swaps
Derivative [Line Items]
Total Notional	258	0
Non-investment Grade | Single name credit default swaps
Derivative [Line Items]
Total Notional	$ 192	$ 261