Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Operating Activities
Earnings (loss)	$ (5,883)	$ (3,858)	$ (17,169)	$ (17,708)
Earnings (loss) from discontinued operations	0	0	0	(570)
Earnings (loss) from continuing operations	(5,883)	(3,858)	(17,169)	(17,138)
Items not affecting cash
Depreciation and amortization	8,254	8,646	24,601	25,955
Amortization of Debt Issuance Costs	613	3,988	1,751	10,210
Deferred income taxes	(3,425)	(5,252)	(13,340)	(19,760)
Stock-based compensation	1,995	1,181	4,133	3,173
Unrealized Loss (Gain) on Derivatives Instrument	754	(749)	(475)	(1,264)
Fair Value of Contingent Consideration	83	124	287	(1,281)
Impairment of long-lived assets	4,467	10,300	8,190	12,035
Acquisition accounting adjustment on inventory sold	0	1,890	0	13,404
Other	55	(64)	(46)	343
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Inventory	0	1,890	0	13,404
Changes in non-cash working capital, net of business acquired	(18,006)	836	(25,319)	(60,943)
Net cash flows from operations - continuing operations	(11,093)	17,042	(17,387)	(35,266)
Net cash flows from operations - discontinued operations	0	0	0	758
Net Cash Provided by (Used in) Operating Activities, Total	(11,093)	17,042	(17,387)	(34,508)
Investing activities
Purchases of property, plant and equipment	(6,527)	(5,463)	(22,694)	(14,803)
Proceeds From Sale Of Property Plant And Equipment	475	0	776	0
Acquisition of non-controlling interest	(1,737)	0	(1,737)	0
Other	5	0	369	700
Net cash flows from investing activities - continuing operations	(7,784)	(5,463)	(23,286)	(14,103)
Net cash flows from investing activities - discontinued operations	0	0	0	1,754
Net cash flows from investing activities	(7,784)	(5,463)	(23,286)	(12,349)
Financing activities
Increase (decrease) under line of credit facilities	19,222	(13,097)	48,571	258,475
Repayment of Line of Credit Facilities	0	0	0	(192,677)
Borrowings under long term debt	417	0	417	432
Repayment of long-term debt	(564)	(520)	(1,680)	(11,529)
Payments Of Dividends	(1,700)	0	(4,991)	0
Proceeds From Stock Options Exercised	1,052	227	4,681	914
Financing costs	(206)	(1,179)	(206)	(5,545)
Payment of contingent consideration	0	0	(4,330)	(4,554)
Other	13	8	(290)	(126)
Net cash flows from financing activities - continuing operations	18,234	(14,561)	42,172	45,390
Cash Provided By Used In Financing Activities Discontinued Operations	0	0	0	(1,180)
Net Cash Provided By (Used In) Financing Activities	18,234	(14,561)	42,172	44,210
Foreign exchange gain (loss) on cash held in a foreign currency	41	329	105	305
Increase (decrease) in cash and cash equivalents during the period	(602)	(2,653)	1,604	(2,342)
Discontinued operations cash activity included above:
Add: Balance included at beginning of period	0	0	0	1,707
Less: Balance included at end of period	0	0	0	0
Cash and cash equivalents - beginning of the period	3,457	4,292	1,251	2,274
Cash and cash equivalents - end of the period	2,855	1,639	2,855	1,639
Noncash Investing And Financing Items [Abstract]
Accrued Dividends	0	0	(1,700)	0
Proceeds of divestiture of business, note receivable	$ 0	$ 0	$ 0	$ 1,537