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Quarterly Data - Schedule of Quarterly Data (Parenthetical) (Detail) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2013 | Jun. 30, 2013 | Dec. 31, 2013
Income Statement [Abstract] |  |  |
Goodwill impairment | $ 1,731,000,000 |  | $ 1,731,000,000
Goodwill impairment after noncontrolling interest | 1,719,000,000 |  |
Discrete income tax charge | 372,000,000 |  |
Charges recorded of settlement amount | 288,000,000 | 0 |
After-tax and noncontrolling interest | $ 243 |  |

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