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Changes in Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Oct. 01, 2017 | Oct. 02, 2016 | Oct. 01, 2017 | Oct. 02, 2016 | Dec. 31, 2016 | Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Amounts reclassified from accumulated other comprehensive income, tax | $ (105) | $ (196) | $ (288) | $ (291) |  |
Foreign currency translation adjustments, tax | 0 | 0 | 0 | 0 | $ 0 | $ 0
Unrealized gains on marketable securities, tax | 1,702 | 1,749 | 1,702 | 1,749 | 209 | (459)
Retirement plans prior service benefit, tax | (893) | (727) | (893) | (727) | $ (778) | $ (622)
Foreign currency translation reclassification adjustments |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Other comprehensive (loss) income before reclassifications, tax |  |  | 0 | 0 |  |
Amounts reclassified from accumulated other comprehensive income, tax |  |  | 0 | 0 |  |
Other comprehensive income (loss), tax |  |  | 0 | 0 |  |
Unrealized Gains (Losses) on Marketable Securities |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Other comprehensive (loss) income before reclassifications, tax |  |  | 1,666 | 2,405 |  |
Amounts reclassified from accumulated other comprehensive income, tax | (67) | (150) | (173) | (152) |  |
Other comprehensive income (loss), tax |  |  | 1,493 | 2,253 |  |
Amortization of prior service credit |  |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |  |
Other comprehensive (loss) income before reclassifications, tax |  |  | 0 | 34 |  |
Amounts reclassified from accumulated other comprehensive income, tax | $ (38) | $ (46) | (115) | (139) |  |
Other comprehensive income (loss), tax |  |  | $ (115) | $ (105) |  |

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- Definition The tax effect from the total of net (gain) loss, prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost. + References No definition available. + Details
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- Definition The tax effect from accumulated adjustment, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains (losses). + References No definition available. + Details
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