Supplemental Cash Flow Information (Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Supplemental Cash Flow Elements [Abstract]
Accounts receivable	$ 5,398	$ 18,768	$ (6,961)	$ 7,641
Inventories	(53,256)	(32,271)	(34,954)	(5,913)
Income tax recoverable/payable	(1,134)	(3,339)	2,207	(4,799)
Prepaid expenses and other current assets	4,322	(4,813)	(1,054)	(9,546)
Accounts payable and accrued liabilities	5,650	(5,715)	6,031	6,695
Customer and other deposits	696	(3,278)	(704)	(1,391)
Increase (Decrease) in Operating Capital	$ (38,324)	$ (30,648)	$ (35,435)	$ (7,313)

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period of all taxes owed but not paid, including income, property and other taxes.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in the amount of (a) prepayments by customers for goods or services to be provided at a later date, (b) the amount of customer money held in customer accounts, including security deposits, collateral for current or future transactions, initial payment of the cost of an acquisition or for the right to enter into a contract or agreement, (c) the increase (decrease) during the reporting period, excluding the portion taken into income, in the liability reflecting services yet to be performed by the reporting entity for which cash or other forms of consideration was received or recorded as a receivable, or (d) some combination of (a), (b), and (c).

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

+ References

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- Definition

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

+ References

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- Definition

Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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- Definition

The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

+ References

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- References

No definition available.

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