Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 25, 2017		Mar. 26, 2016
Cash flows from operating activities:
Net income (loss)	$ 6,763		$ (1,691)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	2,202		2,669
Share-based compensation expense	1,717		1,737
Deferred income taxes	(711)		(535)
Changes in other accrued liabilities	135		28
Changes in other assets	(433)		(26)
Loss on disposal of assets			32
Changes in current assets and liabilities, excluding effects from acquisitions:
Accounts receivable	(15,780)		(5,258)
Inventories	(4,730)		(2,518)
Other current assets	(1,422)		(1,856)
Accounts payable	5,445		5,053
Deferred profit	(2,121)		1,817
Income taxes payable	690		487
Accrued compensation, warranty and other liabilities	1,043		(1,398)
Net cash used in operating activities	(7,202)		(1,459)
Cash flows from investing activities, excluding effects from acquisitions:
Cash paid for Kita, net of cash received	(11,716)
Purchases of short-term investments	(8,080)		(8,891)
Sales and maturities of short-term investments	17,701		967
Purchases of property, plant and equipment	(1,430)		(895)
Cash received from sale of fixed assets			813
Net cash used in investing activities	(3,525)		(8,006)
Cash flows from financing activities:
Cash dividends paid	(1,606)		(1,573)
Repurchases of common stock, net	(957)		(395)
Repayments of long term debt	(470)
Net cash used in financing activities	(3,033)		(1,968)
Effect of exchange rate changes on cash and cash equivalents	1,551		1,008
Net decrease in cash and cash equivalents	(12,209)		(10,425)
Cash and cash equivalents at beginning of period	96,045	[1]	115,370
Cash and cash equivalents at end of period	83,836		104,945
Supplemental disclosure of cash flow information:
Cash paid for income taxes	2,312		248
Inventory capitalized as property, plant and equipment	42		115
Dividends declared but not yet paid	$ 1,614		$ 1,575

[1] Derived from December 31, 2016 audited financial statements