Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019
Cash flows from operating activities:
Net income	$ 18,796	$ 15,967
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	13,456	16,450
Stock-based compensation expense	19,740	7,655
Reduction in the carrying amount of right-of-use assets	2,976	2,907
Amortization of debt issuance costs and discount	208	1,215
Impairment of operating lease right-of-use asset (recorded in Restructuring charges)	0	977
Loss on refinancing of long-term debt	0	2,235
Other non-cash adjustments	(60)	(39)
Changes in assets and liabilities:
Accounts receivable, net	(22,491)	22,997
Inventories	919	2,132
Prepaid expenses and other assets	(1,169)	(5,097)
Accounts payable and accrued expenses	5,207	3,974
Accrued payroll obligations	1,869	(309)
Operating lease liabilities, current and long-term portions	(2,957)	(3,975)
Income taxes payable	370	(593)
Net cash provided by operating activities	36,864	66,496
Cash flows from investing activities:
Proceeds from sales of and maturities of short-term marketable securities	0	9,655
Capital expenditures	(6,829)	(8,459)
Cash paid for software licenses	(4,626)	(3,597)
Net cash used in investing activities	(11,455)	(2,401)
Cash flows from financing activities:
Restricted stock unit tax withholdings	(6,642)	(1,014)
Proceeds from issuance of common stock	4,537	14,037
Proceeds from issuance of long-term debt	50,000	206,500
Original issue discount and debt issuance costs	0	(2,086)
Repayment of debt	(26,250)	(278,033)
Net cash provided by (used in) financing activities	21,645	(60,596)
Effect of exchange rate change on cash	40	86
Net increase in cash and cash equivalents	47,094	3,585
Beginning cash and cash equivalents	118,081	119,051
Ending cash and cash equivalents	165,175	122,636
Supplemental disclosure of cash flow information and non-cash investing and financing activities:
Interest paid	2,193	8,103
Operating lease payments	3,812	4,613
Income taxes paid, net of refunds	1,579	1,500
Accrued purchases of plant and equipment	1,067	1,627
Operating lease right-of-use assets obtained in exchange for lease obligations	$ 1,635	$ 298