v3.3.1.900
Retirement Benefits Plans - Change in Plan Assets (Details 2) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Change in plan assets      
Balance at January 1 $ 4,621    
Balance at December 31 4,406 $ 4,621  
United States pension liabilities [Member]      
Change in plan assets      
Balance at January 1 3,086 2,940  
Actual return on plan assets (55) 226  
Employer contributions 221 248 $ 196
Gross benefits paid (318) (329)  
Currency translation 0 0  
Other 0 1  
Balance at December 31 2,934 3,086 2,940
Non-United States pension liabilities [Member]      
Change in plan assets      
Balance at January 1 1,535 1,432  
Actual return on plan assets 29 191  
Employer contributions 109 114 145
Gross benefits paid (100) (106)  
Currency translation (101) (96)  
Other 0 0  
Balance at December 31 1,472 1,535 1,432
Other postretirement liabilities [Member]      
Change in plan assets      
Balance at January 1 116 138  
Actual return on plan assets 1 4  
Employer contributions 31 40  
Gross benefits paid (86) (91)  
Currency translation 0 0  
Other 31 25  
Balance at December 31 $ 93 $ 116 $ 138