Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Tax benefit on net other comprehensive loss recognized during the period for postretirement benefit plans | $ 668 | $ 192 | $ 1,500 |
| Tax expense on amounts reclassified from accumulated other comprehensive loss during the period for postretirement benefit plans | $ 382 | $ 464 | $ 386 |