Employee Benefits (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Maximum annual increase percentage to company contribution for retiree medical coverage	4.00%
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position	$ 600	$ 600
Defined benefit plan, contributions by employer to employee pension plan	85
Contribution to other post retirement plans	50
Defined benefit plan, expected contributions in current fiscal year	148
U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position		350
Defined benefit plan, contributions by employer to employee pension plan	51
International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, estimated future employer contributions in next fiscal year beginning after the date of the latest statement of financial position		$ 250