Consolidated Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating Activities:
Net income	$ 1,551	$ 11,165
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	20,488	22,217
Deferred income taxes	(913)	3,070
Stock based compensation	3,909	3,291
Defined benefit plan income	(278)	(699)
Allowance for credit losses	605	545
Loss on sale of property and equipment	339	227
Operating lease expense	3,490	2,903
Impairment loss		20,369
Gain on sale of business		(4,970)
Gain on sale of patents	(1,978)
Changes in assets and liabilities:
Accounts receivable	37,805	(4,021)
Inventory	5,292	1,650
Other assets	2,888	276
Accounts payable	(17,753)	(9,528)
Other liabilities	(5,218)	(6,087)
Net cash provided by operating activities	50,227	40,408
Investing Activities:
Purchases of property and equipment	(7,500)	(13,024)
Acquisition of intangible assets	(3,141)
Proceeds from the sale of patents and property and equipment	1,061	82
Proceeds from divestiture of business		47,500
Acquisition of subsidiary, net of cash acquired		(15,476)
Net cash (used in) provided by investing activities	(9,580)	19,082
Financing Activities:
Borrowing of debt	201,193	28,371
Repayments of debt	(81,830)	(61,120)
Cash paid for financing costs		(1,278)
Cash paid for the cancellation of restricted stock	(471)	(926)
Proceeds from the exercise of Common Stock options	6,178	4,771
Cash paid for the repurchase of Common Stock	(9,092)	(33,040)
Net cash provided by (used in) financing activities	115,978	(63,222)
Foreign currency effect	2,102	293
Net increase (decrease) in cash, cash equivalents and restricted cash	158,727	(3,439)
Cash, cash equivalents and restricted cash at beginning of period	52,948	39,620
Cash, cash equivalents and restricted cash at end of period	211,675	36,181
Supplemental disclosure of cash flow information:
Cash (refund) paid for taxes	(3,117)	3,522
Cash paid for interest	$ 1,967	$ 2,712