Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net income (loss)	$ (56,877)	$ 52,415	$ (96,581)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization of intangible assets	97,290	114,400	122,497
Non-cash operating lease expense	18,178	18,958	0
Stock-based compensation	25,053	26,960	31,263
Amortization of prepaid debt fees	4,130	5,631	7,046
Deferred taxes, net	(12,939)	(192)	(19,130)
Loss on sale of business	59,817	0	0
Restructuring, non-cash	5,888	(1,785)	859
Other adjustments, net	10,392	(4,295)	1,452
Increase (Decrease) in Operating Capital [Abstract]
Accounts receivable	108,256	(39,467)	15,524
Inventories	35,403	(9,389)	(25,613)
Other current assets	(11,832)	(31,128)	(23,589)
Other long-term assets	(11,391)	7,053	3,020
Accounts payables, other current liabilities, and taxes payable	(111,724)	9,177	20,101
Wages and benefits payable	(34,664)	30,835	(9,565)
Unearned revenue	8,212	8,905	27,584
Warranty	(13,538)	(6,637)	20,815
Other operating, net	(10,140)	(8,601)	34,072
Net cash provided by operating activities	109,514	172,840	109,755
Investing activities
Net proceeds related to the sale of business	1,133	0
Net proceeds related to the sale of business			0
Acquisitions of property, plant, and equipment	(46,208)	(60,749)	(59,952)
Business acquisitions, net of cash equivalents acquired	0	0	(803,075)
Other investing, net	4,039	12,569	369
Net cash used in investing activities	(41,036)	(48,180)	(862,658)
Financing activities
Proceeds from borrowings	400,000	50,000	778,938
Payments on debt	(414,063)	(137,657)	(363,359)
Issuance of common stock	8,886	24,390	9,171
Repurchase of common stock	0	25,000	0
Prepaid debt fees	(1,571)	(1,560)	(24,042)
Other financing, net	(4,828)	(7,692)	(4,887)
Net cash provided by (used in) financing activities	(11,576)	(97,519)	395,821
Effect of foreign exchange rate changes on cash, cash equivalents, and restricted cash	127	435	(7,925)
Increase (decrease) in cash, cash equivalents, and restricted cash	57,029	27,576	(365,007)
Cash, cash equivalents, and restricted cash at beginning of period	149,904	122,328	487,335
Cash, cash equivalents, and restricted cash at end of period	206,933	149,904	122,328
Supplemental disclosure of cash flow information:
Income taxes, net	2,688	12,041	13,771
Interest	$ 47,241	$ 44,788	$ 42,347