Non-Qualified Deferred Compensation Plan (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 28, 2013 employee		Dec. 31, 2012
Deferred compensation plan - marketable securities [Line Items]
Number of participants NQDC	130
Deferred Compensation Plan Assets	$ 74,737	[1]	$ 77,437	[1]
Level 1 [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	71,713	[1]	74,091	[1]
Level 1 [Member] | Restricted cash equivalents [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	18,984	[1]	17,116	[1]
Level 1 [Member] | Equity securities [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	25,262	[1]	29,902	[1]
Level 1 [Member] | Mutual funds [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	27,467	[1]	27,073	[1]
Level 2 [Member] | Fixed income securities [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	$ 3,024	[1]	$ 3,346	[1]

[1] Included in Deferred compensation plan - marketable securities and Deferred compensation plan - restricted cash equivalents in the accompanying consolidated balance sheets as of June 28, 2013 and December 31, 2012.