Basis Of Presentation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Basis of Presentation [Line Items]
Change in diluted earnings per share due to net favorable/(unfavorable) cumulative catch-up adjustments	$ (0.39)	$ (0.71)	$ (0.70)	$ (0.58)
Increase/(Decrease) in Earnings from operations due to change in accounting estimate	$ (503)	$ (724)	$ (587)	$ (594)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect on Net earnings/(loss)	$ (234)	$ 1,110	$ 985	$ 2,446
Effect on Earnings Per Share, Diluted	$ (0.37)	$ 1.59	$ 1.51	$ 3.46
Effect on Net Cash Provided by Operating Activities			$ 4,465	$ 3,385
Effect on Net Cash used by Financing Activities			(5,809)	$ (5,540)
Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect on Net earnings/(loss)	$ 54		$ 54
Effect on Earnings Per Share, Diluted	$ 0.08		$ 0.08
Effect on Net Cash Provided by Operating Activities			$ 54
Effect on Net Cash used by Financing Activities			$ (54)