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Cash, Cash Equivalents, and Investments (Detail) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Oct. 02, 2016 | Oct. 04, 2015 | Oct. 02, 2016 | Oct. 04, 2015
Cash and Cash Equivalents [Abstract] |  |  |  |
Gross realized gains on sale of investments | $ 55,000 | $ 26,000 | $ 280,000 | $ 434,000
Gross realized losses on sale of investments | 0 | $ 7,000 | 97,000 | $ 194,000
Maximum amount committed to invest in limited partnership |  |  | 20,500,000 |
Contribution to limited partnership | 19,886,000 |  | $ 19,886,000 |
Investment expiration date |  |  | Dec. 31, 2017 |
Remaining amount of commitment in limited partnership | $ 614,000 |  | $ 614,000 |
Contributions made during the period |  |  | 0 |
Distributions received during the period |  |  | 1,492,000 |
Partners' Capital Account, Return of Capital |  |  | 942,000 |
Cost-method Investments, Realized Gains |  |  | $ 550,000 |

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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
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- Definition For investments in debt and equity securities accounted for at cost, the excess of net sale proceeds over the carrying amount of investments disposed of during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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