BUSINESS SEGMENT INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Mar. 29, 2014
Reconciliation of segment income to consolidated income before income taxes
Segment income	$ 13,629us-gaap_OperatingIncomeLoss	$ 12,526us-gaap_OperatingIncomeLoss
(Loss) gain on disposal of assets	(1,088)us-gaap_GainLossOnDispositionOfAssets1	411us-gaap_GainLossOnDispositionOfAssets1
Interest and other expense, net	(903)us-gaap_OtherNonoperatingIncomeExpense	(976)us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	12,726	11,550
Operating segments
Reconciliation of segment income to consolidated income before income taxes
Segment income	27,436	23,682
Unallocated amount to segment
Reconciliation of segment income to consolidated income before income taxes
Unallocated operating expenses	$ (12,719)	$ (11,567)

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

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 210.5-03.9)

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