Non-Qualified Deferred Compensation Plan (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 27, 2015 employee		Dec. 31, 2014
Deferred compensation plan - marketable securities [Line Items]
Number of participants NQDC	122
Deferred Compensation Plan Assets	$ 85,301	[1]	$ 83,779	[1]
Level 1 [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	83,421	[1]	81,697	[1]
Level 1 [Member] | Restricted cash equivalents [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	20,226	[1]	14,412	[1]
Level 1 [Member] | Equity securities [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	30,314	[1]	33,521	[1]
Level 1 [Member] | Mutual funds [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	32,881	[1]	33,764	[1]
Level 2 [Member] | Fixed income securities [Member]
Deferred compensation plan - marketable securities [Line Items]
Deferred Compensation Plan Assets	$ 1,880	[1]	$ 2,082	[1]

[1] Included in Deferred compensation plan—marketable securities and Deferred compensation plan—restricted cash equivalents in the accompanying consolidated balance sheets as of March 27, 2015 and December 31, 2014.