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Note 6 - Investment in Unconsolidated Affiliate (Details Textual) - USD ($)	1 Months Ended		3 Months Ended											12 Months Ended
	Nov. 30, 2012	Apr. 30, 2012	Jan. 02, 2016	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Mar. 30, 2013	Dec. 29, 2012	Jan. 02, 2016	Jan. 02, 2016	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Shocking [Member] \| Equity Method Investments [Member]
Operating Income (Loss)																		$ 4,000,000
Other than Temporary Impairment Losses, Investments												$ 8,700,000
Shocking [Member] \| Loans Receivable [Member]
Other than Temporary Impairment Losses, Investments												2,000,000
Shocking [Member]
Investments in and Advances to Affiliates, at Fair Value, Gross Additions		$ 10,000,000
Investments in and Advances to Affiliates, at Fair Value		$ 16,000,000
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		18.40%
Increase (Decrease) in Notes Receivables	$ 2,000,000
Other than Temporary Impairment Losses, Investments												10,700,000
Investments												$ 0
Income Taxes Paid, Net											$ 6,100,000
Income Tax Expense (Benefit)											$ 3,300,000		$ 2,800,000
Operating Income (Loss)			$ 29,854,000	$ 8,584,000	$ 36,171,000	$ 29,548,000	$ 26,391,000	$ 40,130,000	$ 33,719,000	$ 33,590,000				$ 104,157,000	$ 104,157,000	$ 133,830,000	$ 129,881,000
Income Tax Expense (Benefit)														$ 24,482,000	$ 24,482,000	$ 32,228,000	$ 35,451,000