Accrued Expenses And Other Payables (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Unrealized losses on derivative contracts	$ 651	$ 605
Reinsurance Payable	479	425
Liability for Claims and Claims Adjustment Expense	373	459
Deferred income	1,065	1,152
Other accruals and payables	1,414	1,472
Total accrued expenses and other payables	$ 3,982	$ 4,113