Fair Value Measurements (Narrative) (Details) (USD $)	Sep. 27, 2014	Dec. 28, 2013
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured and recorded at fair value	$ 0
Liabilities measured and recorded at fair value	0
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments previously listed as Level 2	300,000
Assets measured and recorded at fair value	124,907,000	125,748,000
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments previously listed as Level 1	15,500,000
Assets measured and recorded at fair value	25,778,000	3,166,000
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured and recorded at fair value	0
Liabilities measured and recorded at fair value	$ 0