|
Schedule of Quarterly Financial Information (Parenthetical) (Detail) (USD $)
In Billions, unless otherwise specified |
3 Months Ended | ||||
|---|---|---|---|---|---|
|
Jun. 30, 2013
Pension remeasurement charge
|
Sep. 30, 2012
Legal Settlement
|
Dec. 31, 2012
Severance, pension and benefit charges and costs related to the early redemption of debt
|
Dec. 31, 2013
Severance, Pension and Benefit Credit
|
Dec. 31, 2013
Wireless Transaction Costs
|
|
| Quarterly Financial Information [Line Items] | |||||
| After-tax credits (charges) included in consolidated results of operations | $ 0.1 | $ (0.2) | $ (5.3) | $ 3.7 | $ (0.5) |