Fair value Measurement (Narrative) (Details) (USD $)	6 Months Ended
Jun. 26, 2011
Fair Value Measurement
Net asset value	$ 1.00
Pay-outs resulted in additional accrual	100,000
Contingent consideration in other current liabilities	3,900,000
Contingent consideration in other liabilities	$ 5,600,000

The net increase or decrease during the period to the fair value of certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) measured based on unobservable inputs (Level 3). Such movements may include gains and losses which were realized or unrealized and included in earnings or recognized as a change in net assets; movements in the Level 3 alternative investments due to purchases, sales, issuances, or settlements; or transfers in or out of the Level 3 category for purposes of measuring fair value (for example, due to a change in the observability of significant inputs).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration