Retirement Plans (Details Textuals) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Defined contribution retirement plans [Member] | |||
| Retirement Plans (Textuals) [Abstract] | |||
| Total expense for all defined contribution retirement plans | $ 224 | $ 272 | $ 281 |
| Defined benefit pension and other postretirement benefit plans [Member] | |||
| Retirement Plans (Textuals) [Abstract] | |||
| Net funded status related to the defined benefit pension plans | 770 | 767 | |
| Total expense for all defined contribution retirement plans | $ 23 | $ 24 | $ 59 |