Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 26, 2021	Jun. 27, 2020
Cash flows from operating activities:
Net income (loss)	$ 122,703	$ (22,016)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Gain on business divestitures	(75,664)	(35)
Loss on extinguishment of debt	1,761	0
Impairment charges related to indefinite lived intangibles	0	3,949
(Gain) loss from sale of property, plant and equipment	(55)	112
Depreciation and amortization	24,997	26,038
Share-based compensation expense	7,029	7,014
Non-cash inventory related charges	2,690	1,675
Deferred income taxes	459	(4,855)
Changes in accrued retiree medical benefits	45	452
Changes in other accrued liabilities	(72)	(291)
Changes in other assets	(219)	1,246
Amortization of cloud-based software implementation costs	748	513
Interest capitalized associated with cloud computing implementation	(85)	(76)
Amortization of debt discounts and issuance costs	441	592
Changes in assets and liabilities:
Customer advances	(3,776)	5,588
Accounts receivable	(80,118)	6,439
Inventories	(25,633)	(13,130)
Other current assets	(1,852)	(359)
Accounts payable	39,611	6,788
Deferred profit	8,912	1,934
Income taxes payable	15,731	(181)
Accrued compensation, warranty and other liabilities	368	(7,994)
Operating lease right-of-use assets	3,919	3,517
Current and long-term operating lease liabilities	(6,319)	(3,631)
Net cash provided by operating activities	35,621	13,289
Cash flows from investing activities:
Cash received from disposition of business, net of cash paid	120,137	2,975
Cash received from sale of property, plant and equipment	106	2,525
Purchases of short-term investments	(136,526)	0
Sales and maturities of short-term investments	77,014	0
Purchases of property, plant and equipment	(5,549)	(7,963)
Net cash provided by (used in) investing activities	55,182	(2,463)
Cash flows from financing activities:
Cash dividends paid	0	(4,971)
Issuance (repurchases) of common stock, net	(5,622)	206
Proceeds from revolving line of credit and construction loans	818	4,345
Proceeds received from issuance of common stock, net of fees	223,119	0
Repayments of long-term debt	(104,811)	(2,162)
Net cash provided by (used in) financing activities	113,504	(2,582)
Effect of exchange rate changes on cash and cash equivalents	231	(1,446)
Net increase in cash and cash equivalents	204,538	6,798
Cash and cash equivalents at beginning of period	149,358	155,930
Cash and cash equivalents at end of period	353,896	162,728
Supplemental disclosure of cash flow information:
Cash paid for income taxes	3,747	2,103
Inventory capitalized as property, plant and equipment	997	339
Business divestiture expenses included in other liabilities	5,266	0
Property, plant and equipment purchases included in accounts payable	690	2,327
Capitalized cloud computing service costs included in accounts payable	1,192	2,265
Cash paid for interest	$ 4,180	$ 10,842