CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 25, 2011	Jun. 30, 2012	Jun. 25, 2011
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	$ 37	$ 157	$ 137	$ 161

Tax effect of the appreciation (loss) in the value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) losses.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580

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Data Type:	xbrli:monetaryItemType
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