Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016
OPERATING ACTIVITIES
Net income	$ 13,742	$ 7,685
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	7,345	6,476
Amortization	6,216	5,098
Bad debt recovery	(319)	(853)
Loss on write down of inventory	1,068	4,011
Compensation expense of share-based plans	1,386	2,909
Tax effect of share-based plan compensation	0	(116)
Fair Value, Instruments Classified in Shareholders' Equity Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(12,200)	0
(Gain) Loss on sale or write down of property, plant and equipment	(66)	3,116
Gain (Loss) on Disposition of Business	5,300	0
Changes in operating assets and liabilities, net of effects of acquisition:
Trade accounts receivable	16,478	11,555
Inventories	(12,382)	13,281
Prepaid expenses and other assets	(8,011)	(3,480)
Accounts payable, accrued expenses and other liabilities	305	(32,161)
Net cash provided by operating activities	18,862	17,753
INVESTING ACTIVITIES
Purchases of property, plant and equipment	(5,504)	(6,998)
Proceeds from the sale of property, plant and equipment	318	1,138
Goodwill, Purchase Accounting Adjustments	1,467	0
Net cash used in investing activities	(3,719)	(5,860)
FINANCING ACTIVITIES
Proceeds from long-term debt	333,021	65,939
Payments of long-term debt	(332,233)	(58,890)
Debt issuance costs	450	0
Dividends paid	(1,251)	(1,249)
Proceeds from the exercise of stock options	707	180
Tax effect of share-based plan compensation	0	(116)
Net cash (used in) provided by financing activities	(206)	5,864
Effect of exchange rate changes on cash and cash equivalents	4,056	672
INCREASE IN CASH AND CASH EQUIVALENTS	18,993	18,429
Cash and cash equivalents at beginning of period	58,279	54,541
FINANCING ACTIVITIES	77,272	72,970
Non-cash investing activities:
Purchases of property and equipment included in accounts payable and accrued expenses	618	1,418
Debt issuance costs included in accounts payable and accrued expenses	277	0
Debt issuance costs funded through New Credit Agreement	1,262	0
Energy Segment [Member]
INVESTING ACTIVITIES
Purchases of property, plant and equipment	$ (1,496)	$ (1,555)