Income Tax (Details Textuals) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Taxes (Textuals) [Abstract]
Possible decrease in unrecognized tax benefits as a result of potential resolutions of prior years' tax	$ 294		$ 294
Unrecognized tax benefits, amounts recorded to equity, if recognized	$ 289		$ 289
Effective tax rate	14.30%	13.30%	12.50%	15.20%
U.S. statutory federal income tax rate			35.00%
Out of period tax adjustment				$ 11
Internal Revenue Service (IRS) [Member] | Earliest Year [Member]
Income Tax Contingency [Line Items]
Open tax years by major tax jurisdiction			2008
Internal Revenue Service (IRS) [Member] | Latest Year [Member]
Income Tax Contingency [Line Items]
Open tax years by major tax jurisdiction			2014