Long-Term Employee Benefits (Contributions) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Principal U.S. Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		$ 0	$ 500	$ 0
Expected contributions in next fiscal year	0
Pension Plan Other Than Principal U.S. Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		313
Expected contributions in next fiscal year	344
Other Long-Term Employee Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		207
Expected contributions in next fiscal year	$ 224