Income Taxes (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Components of Deferred Tax Assets [Abstract]
Net Operating Loss Carryforwards	$ 6,024	$ 6,414
Pension, Postretirement and Other Benefits	4,982	6,415
AMT Credit Carryforward	378	402
Deferred Revenue	1,965	2,133
Other	698	881
Valuation Allowance	(177)	(10,963)
Deferred Tax Assets, Net of Valuation Allowance	13,870	5,282
Components of Deferred Tax Liabilities [Abstract]
Depreciation	4,799	4,851
Intangible Assets	1,704	1,730
Other	639	285
Total Deferred Tax Liabilities	7,142	6,866
Deferred Tax Assets, Net, Classification [Abstract]
Deferred income taxes, net	1,736	463
Deferred income taxes, net	4,992	0
Deferred income taxes, net	0	(2,047)
Deferred Tax Assets, Net	$ 6,728	$ (1,584)