Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 27, 2020	Mar. 29, 2019
Cash flows from operating activities:
Net (loss) income	$ (3,103)	$ 16,906
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation, depletion, and amortization	14,274	9,067
Amortization of deferred financing costs in interest expense	182	236
Stock-based compensation expense (non-cash)	1,492	1,547
Deferred income tax expense (benefit)	(1,227)	371
Held-for-sale impairment charges	10,766	0
Changes in assets and liabilities:
Decrease (increase) in accounts receivable	11,049	(14,698)
Decrease (increase) in inventory	(16,723)	(9,561)
Decrease (increase) in prepaid and other current assets	1,127	(556)
Increase (decrease) in accounts payable and accrued expenses	(13,002)	(16,030)
Increase (decrease) in unearned revenue	(938)	(724)
Increase (decrease) in interest and taxes payable	368	2,525
Domestic pension plan contributions	0	(1,500)
Other-net	4,865	(200)
Net cash used in operating activities	9,130	(12,617)
Cash flows from investing activities:
Payments for purchase of property, plant, and equipment	(14,789)	(8,027)
Payments for mine development	0	1,352
Proceeds from sale of property, plant, and equipment	10	58
Net cash used in investing activities	(14,779)	(9,321)
Cash flows from financing activities:
Repayment of long-term debt	(142)	(197)
Principal payments under finance lease obligations	233	298
Cash dividends paid	(2,245)	(2,125)
Repurchase of common stock	(6,766)	(199)
Payments of withholding taxes for stock-based compensation awards	(2,015)	(3,978)
Net cash used in financing activities	(11,401)	(6,797)
Effects of exchange rate changes	(381)	(46)
Net change in cash and cash equivalents	(17,431)	(28,781)
Cash and cash equivalents at beginning of period	125,007	70,645
Cash and cash equivalents at end of period	$ 107,576	$ 41,864