CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 462	$ 564
Product warranty, measured at fair value, current	8,267	6,794
Product warranty, measured at fair value, noncurrent	$ 20,469	$ 13,012
Common stock, par value (in usd per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	200,000,000	150,000,000
Common stock, shares issued (in shares)	128,962,000	123,109,000
Common stock, shares outstanding (in shares)	128,962,000	123,109,000