Condensed Consolidated Statements of Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	[1]	Jun. 30, 2022	Jun. 30, 2021	[1]
Income Statement [Abstract]
Net sales	$ 254,151	$ 264,483		$ 494,326	$ 512,086
Cost of sales	69,801	92,204		141,533	176,399
Gross profit	184,350	172,279		352,793	335,687
Operating expenses:
Selling, general and administrative	116,482	122,748		235,007	238,429
Research and development	34,229	52,557		75,147	97,182
Other operating expenses	1,883	33,236		1,378	42,036
Operating income (loss)	31,756	(36,262)		41,261	(41,960)
Interest expense	(14,388)	(16,515)		(22,228)	(32,451)
Foreign exchange and other income/(expense)	1,633	239		5,537	(6,204)
Income (loss) before tax	19,001	(52,538)		24,570	(80,615)
Income tax expense	2,515	3,908		5,052	6,552
Losses from equity method investments	(42)	(41)		(81)	(81)
Net income (loss)	$ 16,444	$ (56,487)	[2]	$ 19,437	$ (87,248)	[2],[3]
Basic loss per share (in dollars per share)	$ 0.31	$ (1.15)		$ 0.36	$ (1.79)
Diluted loss per share (in dollars per share)	$ 0.30	$ (1.15)		$ 0.36	$ (1.79)
Shares used in computing basic loss per share (in shares)	53,506	48,928		53,420	48,833
Shares used in computing diluted loss per share (in shares)	54,080	48,928		54,144	48,833

[1] The condensed consolidated statements of income (loss) for the three and six months ended June 30, 2021 have been revised. For further details refer to “Note 1. Unaudited Condensed Consolidated Financial Statements.”

[2] The condensed consolidated statements of comprehensive income (loss) for the three and six months ended June 30, 2021 have been revised. For further details refer to “Note 1. Unaudited Condensed Consolidated Financial Statements.”

[3] The condensed consolidated statement of cash flows for the three and six months ended June 30, 2021 have been revised. For further details refer to “Note 1. Unaudited Condensed Consolidated Financial Statements.”