Summary of Significant Accounting Policies (Details 5) - USD ($)		Jan. 02, 2016	Dec. 27, 2014
Level 1 [Member]
Asset
Financial Liabilities Fair Value Disclosure		$ 0
Level 2 [Member]
Asset
Financial Liabilities Fair Value Disclosure		28,000
Level 3 [Member]
Asset
Financial Liabilities Fair Value Disclosure		0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Asset
Total assets measured at fair value		110,817,000	$ 109,843,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Money Market Funds [Member]
Asset
Total assets measured at fair value		110,817,000	109,843,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Asset
Total assets measured at fair value		33,124,000	36,166,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Bonds [Member]
Asset
Total assets measured at fair value	[1]	33,124,000	$ 36,166,000
Derivative Financial Instruments, Liabilities [Member] | Level 1 [Member]
Asset
Financial Liabilities Fair Value Disclosure	[2]	0
Derivative Financial Instruments, Liabilities [Member] | Level 2 [Member]
Asset
Financial Liabilities Fair Value Disclosure	[2]	28,000
Derivative Financial Instruments, Liabilities [Member] | Level 3 [Member]
Asset
Financial Liabilities Fair Value Disclosure	[2]	$ 0

[1] (1) The bond investments are valued based on observable market values as of the Company's reporting date. The bond investments are recorded at fair value and marked-to-market at the end of each reporting period. The realized and unrealized gains and losses are included in comprehensive income for that period.

[2] (2) Derivative instruments are valued using an income approach based on the present value of the forward rate less the contract rate multiplied by the notional amount.