|
Summary of Reconciliation of Segment Operating Revenues (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2013
|
Sep. 30, 2013
|
Jun. 30, 2013
|
Mar. 31, 2013
|
Dec. 31, 2012
|
Sep. 30, 2012
|
Jun. 30, 2012
|
Mar. 31, 2012
|
Dec. 31, 2013
|
Dec. 31, 2012
|
Dec. 31, 2011
|
|
| Segment Reporting, Revenue Reconciling Item [Line Items] | |||||||||||
| Operating Revenues | $ 31,065 | $ 30,279 | $ 29,786 | $ 29,420 | $ 30,045 | $ 29,007 | $ 28,552 | $ 28,242 | $ 120,550 | $ 115,846 | $ 110,875 |
|
Operating Segments
|
|||||||||||
| Segment Reporting, Revenue Reconciling Item [Line Items] | |||||||||||
| Operating Revenues | 120,246 | 115,648 | 110,836 | ||||||||
|
Corporate, Eliminations and Other
|
|||||||||||
| Segment Reporting, Revenue Reconciling Item [Line Items] | |||||||||||
| Operating Revenues | $ 304 | $ 198 | $ 39 | ||||||||