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Summary Of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Apr. 02, 2017 | Jan. 01, 2017 | Dec. 31, 2016
New Accounting Pronouncements |  |  |
New Accounting Pronouncement, Cumulative Effect of Change on Equity |  |  | $ 3
Length of fiscal quarters, weeks | 91 days |  |
Accounting Standards Update 2016-16 |  |  |
New Accounting Pronouncements |  |  |
New Accounting Pronouncement, Cumulative Effect of Change on Equity |  | $ 3 |

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