Condensed Consolidated Statements of Cash Flows - Unaudited - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Cash provided by (used in) operating activities	$ (2,517)	$ 1,066
Net cash provided by (used in) operating activities	(2,517)	1,066
Investing activities:
Proceeds from sale of property, plant and equipment	0	23
Net cash provided by investing activities	0	23
Financing activities:
Purchases of treasury stock	(129)	(986)
Net cash used in financing activities	(129)	(986)
Increase (decrease) in cash and cash equivalents	(2,646)	103
Cash and cash equivalents, beginning of the period	28,181	9,388
Cash and cash equivalents, end of the period	$ 25,535	$ 9,491

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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