Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021		Sep. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 83,210		$ 60,728
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	66,564		64,037
Operatingleaserightofuseassetamortization	7,165		6,859
Provision for doubtful accounts	342		2,785
Provision for warranty and returns	752		(1,296)
Stock compensation	19,236		18,614
Loss on disposal of property and equipment	1,083		1,673
Bond premium amortization	514		126
Debt Issuance Costs amortization	216		216
Change in fair value of contingent earn-out	0		7,000
Inventory Recall Expense	3,380		2,626
Sparepartsusage	9,831		8,391
Other Noncash Income (Expense)	2,908		2,523
Cash provided by (used in) changes in operating assets and liabilities
Accounts receivable	3,807		38,933
Inventories	16,510		8,859
Prepaid expenses and other assets	3,557		(6,535)
Increase (Decrease) in Other Operating Assets	(13,593)		(12,121)
Accounts payable	(10,374)		(38,032)
Accrued liabilities	(8,317)		(20,417)
Income taxes, including excess tax benefits and deferred income taxes	(1,874)		(743)
Net cash provided by operating activities	184,917		144,226
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(46,464)		(62,362)
Proceeds from sale of asset	218		154
Intangible assets additions	(10,216)		(6,325)
Payments to Acquire Equity Method Investments	(3,250)		0
Purchases of investment securities	(10,034)		(9,603)
Proceeds from sale of investment securities	12,000		20,900
Net cash used in investing activities	(57,746)		(57,236)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Lines of Credit	0		150,000
Repayments of Short-term Debt	0		(150,000)
Proceeds from exercise of stock options	6,966		8,586
Finance Lease, Principal Payments	(448)		(231)
Payment, Tax Withholding, Share-based Payment Arrangement	8,109		12,821
Net cash (used in) provided by financing activities	(1,591)		(4,466)
Effect of exchange rate changes on cash	(2,192)		(201)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	123,388		82,323
CASH AND CASH EQUIVALENTS, beginning of period	396,097	[1]	268,670
CASH AND CASH EQUIVALENTS, end of period	519,485		350,993
NON-CASH INVESTING ACTIVITIES
Capital Expenditures Incurred but Not yet Paid	2,897		3,633
Liabilities Assumed	$ 3,100		$ 0

[1] December 31, 2020 balances were derived from audited consolidated financial statements.