Changes in Carrying Amount of Goodwill (Detail) $ in Millions |
6 Months Ended |
|---|---|
|
Jun. 30, 2017
USD ($)
| |
| Goodwill [Line Items] | |
| Beginning balance | $ 27,205 |
| Acquisitions (Note 2) | 1,324 |
| Reclassifications, adjustments and other | (2) |
| Ending balance | 28,527 |
| Wireless | |
| Goodwill [Line Items] | |
| Beginning balance | 18,393 |
| Acquisitions (Note 2) | 5 |
| Ending balance | 18,398 |
| Wireline | |
| Goodwill [Line Items] | |
| Beginning balance | 3,784 |
| Acquisitions (Note 2) | 432 |
| Reclassifications, adjustments and other | (5) |
| Ending balance | 4,211 |
| Other Operating Segments | |
| Goodwill [Line Items] | |
| Beginning balance | 5,028 |
| Acquisitions (Note 2) | 887 |
| Reclassifications, adjustments and other | 3 |
| Ending balance | $ 5,918 |