Consolidated Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating Activities:
Net income	$ 25,697	$ 27,052
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	30,777	33,281
Deferred income taxes	3,583	5,072
Non-cash stock based compensation	6,569	5,268
Defined benefit pension plan income	(433)	(754)
Loss on sale of property and equipment	562	319
Operating lease expense	5,156	4,477
Gain on sale of patents	(1,978)
Impairment loss		21,206
Gain on sale of business		(4,970)
Other		189
Changes in assets and liabilities:
Accounts receivable, net	(33,250)	(5,961)
Inventory	4,645	(5,512)
Other assets	(4,655)	9,594
Accounts payable	24,272	(3,097)
Other liabilities	12,356	(2,172)
Net cash provided by operating activities	73,301	83,992
Investing Activities:
Purchases of property and equipment	(11,613)	(18,340)
Acquisition of intangible assets	(3,141)
Proceeds from the sale of patents and property and equipment	1,068	137
Proceeds from divestiture of business		47,500
Acquisition of subsidiary, net of cash acquired		(14,823)
Net cash (used in) provided by investing activities	(13,686)	14,474
Financing Activities:
Borrowing of debt	201,193	29,470
Repayments of debt	(87,688)	(69,049)
Cash paid for the repurchase of Common Stock	(9,092)	(58,040)
Proceeds from the exercise of Common Stock options	6,828	13,879
Cash paid for the cancellation of restricted stock	(811)	(1,213)
Acquisition contingent consideration payment	(618)
Cash paid for financing costs		(1,278)
Net cash provided by (used in) financing activities	109,812	(86,231)
Foreign currency effect	6,664	(4,151)
Net increase in cash, cash equivalents and restricted cash	176,091	8,084
Cash, cash equivalents and restricted cash at beginning of period	52,948	39,620
Cash, cash equivalents and restricted cash at end of period	229,039	47,704
Supplemental disclosure of cash flow information:
Cash (refund) paid for taxes	(252)	6,676
Cash paid for interest	$ 3,006	$ 3,437