Stockholders' Equity (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Amounts Reclassified from AOCI
Interest expense	$ (831)	$ (32)	$ (1,673)	$ (65)
Interest income	152	363	487	860
Income before income taxes	18,464	17,789	38,542	34,906
Income tax (provision) benefit	(5,852)	2,720	(5,896)	(77)
Net income	12,612	20,509	32,646	34,829
Reclassifications From Accumulated Other Comprehensive Loss
Amounts Reclassified from AOCI
Income before income taxes	91	(447)	(90)	(880)
Income tax (provision) benefit	(32)	156	32	308
Net income	59	(291)	(58)	(572)
Losses on cash flow hedge \| Reclassifications From Accumulated Other Comprehensive Loss
Amounts Reclassified from AOCI
Rent expense		(447)		880
Interest expense	(141)		(322)
Gains on available-for-sales securities \| Reclassifications From Accumulated Other Comprehensive Loss
Amounts Reclassified from AOCI
Interest income	$ 232		$ 232

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

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-Name Statement of Financial Accounting Standard (FAS)

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Income derived from investments in debt securities and on cash and cash equivalents the earnings of which reflect the time value of money or transactions in which the payments are for the use or forbearance of money.

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Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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