Product Warranty (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Product Warranties Disclosures [Abstract]

Schedule of movement of product warranty

	Three Months Ended September 30,						Nine Months Ended September 30,
	2020			2021			2020			2021
Balance at beginning of the period	$	17,358		$	25,543		$	18,416		$	19,356
Provided for new sales during the period		1,517			1,498			2,468			3,761
Provided for pre-existing legacy product		—			34,055			—			40,849
Utilized during the period		(313	)		(9,229	)		(2,322	)		(12,099	)
Balance at end of the period	$	18,562		$	51,867		$	18,562		$	51,867

	December 31, 2019			December 31, 2020
Balance at beginning of the year	$	16,565		$	18,416
Provided during the year		3,501			3,477
Utilized during the year		(1,650	)		(2,537	)
Balance at end of the year	$	18,416		$	19,356
Product warranty – current	$	3,723		$	4,296
Product warranty – non-current		14,693			15,060

Schedule of warranty cost

	December 31, 2020		September 30, 2021
Product warranty – current	$	4,296	$	18,690
Product warranty – non-current		15,060		33,177
Total	$	19,356	$	51,867