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v3.3.1.900

Accounting Standards - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2014 USD ($)
Accounting Changes and Error Corrections [Abstract] |
Decrease in current deferred tax assets | $ 181
Decrease in current deferred tax liabilities | 21
Decrease in long-term deferred tax liabilities | 79
Increase in long-term deferred tax assets | $ 81

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