Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Line Items]
Effective income tax rate		51.10%	31.60%	21.90%	31.50%
Estimated annual effective tax rate excluding discrete items				27.20%
Tax Adjustments, Settlements, and Unusual Provisions				$ 66
Effect on Net earnings/(loss)		$ (234)	$ 1,110	985	$ 2,446
Subsequent Event [Member]
Income Tax Disclosure [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions	$ 180
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 220
Adjustments for New Accounting Pronouncement [Member]
Income Tax Disclosure [Line Items]
Effect on Net earnings/(loss)		$ 54		$ 54