Revenue (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Jan. 01, 2018 |
|
| Revenue, Initial Application Period Cumulative Effect Transition | ||||||||||||
| Retained earnings | $ 40,636 | $ 39,115 | $ 40,636 | $ 39,115 | ||||||||
| Contract Balance | ||||||||||||
| Current deferred income balances | 617 | 513 | 617 | 513 | ||||||||
| Net Sales | $ 7,945 | $ 8,152 | $ 8,390 | $ 8,278 | $ 7,990 | $ 8,172 | $ 7,810 | $ 7,685 | 32,765 | $ 31,657 | $ 30,109 | |
| Difference between Revenue Guidance in Effect before and after Topic 606 | Maximum | ||||||||||||
| Revenue, Initial Application Period Cumulative Effect Transition | ||||||||||||
| Retained earnings | $ 2 | |||||||||||
| ASU 2014-09 Revenue from Contracts with Customers | Difference between Revenue Guidance in Effect before and after Topic 606 | ||||||||||||
| Contract Balance | ||||||||||||
| Deferred income recognized as revenue | $ 500 | |||||||||||