Condensed Consolidated Statements of Cash Flows - Unaudited - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net cash provided by (used in) operating activities	$ 8,966	$ (2,272)
Investing activities:
Purchases of property, plant and equipment	0	(17)
Net cash used in investing activities	0	(17)
Financing activities:
Purchases of treasury stock	(4,340)	(4,985)
Net cash used in financing activities	(4,340)	(4,985)
Increase (decrease) in cash and cash equivalents	4,626	(7,274)
Cash and cash equivalents, beginning of the period	12,550	37,128
Cash and cash equivalents, end of the period	$ 17,176	$ 29,854

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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