Supplemental cash flow information (Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Increase (Decrease) Operating Capital [Line Items]
Increase (Decrease) in Receivables	$ 17,404	$ (17,881)	$ (755)
Increase (Decrease) in Inventories	(25,732)	(10,380)	(9,070)
Increase (Decrease) in Accrued Taxes Payable	(9,782)	3,735	(4,760)
Increase (Decrease) in Prepaid Expense and Other Assets	(2,044)	(2,152)	2,163
Increase (Decrease) in Accounts Payable and Accrued Liabilities	15,242	1,842	7,037
Increase (Decrease) in Deferred Revenue and Customer Advances and Deposits	1,227	518	(1,157)
Increase (Decrease) In Operating Capital	(3,685)	(24,318)	(6,542)
Interest Paid	10,496	3,725	3,845
Income Taxes Paid, Net	10,526	12,351	8,539
Cash and cash equivalents	$ 2,274	$ 7,768	$ 4,453	$ 2,874

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3044-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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