DEBT (Details) $ in Thousands, ¥ in Millions		9 Months Ended	12 Months Ended
		Aug. 01, 2021 USD ($) Tool	Oct. 31, 2020 USD ($)	Aug. 01, 2021 CNY (¥)	Feb. 28, 2021 USD ($)	Dec. 31, 2020 USD ($)	Nov. 30, 2018 CNY (¥)
Debt Instruments [Abstract]
Short-term debt		$ 0	$ 4,708
Weighted-average interest rate of short -term debt			2.02%
Long Term Debt Maturing In Year One [Abstract]
Next 12 months		25,163	$ 8,970
Long-term Debt [Abstract]
Months 13 - 24		25,051	15,142
Months 25 - 36		21,392	13,406
Months 37 - 48		37,153	9,789
Months 49 - 60		9,144	9,432
Thereafter			7,211
Long-term debt		92,740	54,980
Finance lease amount		39,814	0
Xiamen Project Loans [Member]
Long Term Debt Maturing In Year One [Abstract]
Next 12 months		7,615	6,705
Long-term Debt [Abstract]
Months 13 - 24		9,961	7,334
Months 25 - 36		10,165	9,592
Months 37 - 48		9,794	9,789
Months 49 - 60		7,489	9,432
Thereafter			7,211
Long-term debt		$ 37,409	$ 43,358
Interest rate at balance sheet date		4.65%	4.90%
Basis spread on interest rates		0.00%	0.25%
Maturity date		Dec. 31, 2025
Periodic payment amount		Increases as loans mature
Periodic payment frequency		Semiannual, on individual loans
Loan collateral (carrying amount)		$ 91,277	$ 94,459
Maximum borrowing capacity | ¥							¥ 345.0
Amount outstanding		45,000		¥ 291.0
Xiamen Working Capital Loans [Member]
Long Term Debt Maturing In Year One [Abstract]
Next 12 months		8,108	2,265
Long-term Debt [Abstract]
Months 13 - 24		3,961	7,808
Months 25 - 36		0	3,814
Months 37 - 48		0	0
Months 49 - 60		0	0
Thereafter			0
Long-term debt		$ 3,961	$ 11,622
Maturity date		Jul. 31, 2023
Periodic payment amount		Increases as loans mature
Periodic payment frequency		Semiannual, on individual loans
Maximum borrowing capacity		$ 25,000
Expiration date		Oct. 31, 2021
Amount outstanding		$ 12,100		78.0
Xiamen Working Capital Loans [Member] | Minimum [Member]
Long-term Debt [Abstract]
Interest rate at balance sheet date		4.53%	4.53%
Basis spread on interest rates		0.6775%	0.40%
Xiamen Working Capital Loans [Member] | Maximum [Member]
Long-term Debt [Abstract]
Interest rate at balance sheet date		4.61%	4.61%
Basis spread on interest rates		0.76%	0.76%
Hefei Equipment Loan [Member]
Long Term Debt Maturing In Year One [Abstract]
Next 12 months		$ 2,321
Long-term Debt [Abstract]
Months 13 - 24		4,642
Months 25 - 36		4,642
Months 37 - 48		7,736
Months 49 - 60		1,655
Long-term debt		$ 18,675
Interest rate at balance sheet date		4.20%
Basis spread on interest rates		(0.45%)
Maturity date		Sep. 30, 2026
Periodic payment amount	[1]	Varies
Periodic payment frequency	[2]	Semiannual
Loan collateral (carrying amount)		$ 86,892
Percent of repayment on approved loan principal in each first five semiannual loan repayments		7.50%
Percent of repayment on original approved loan amount in each last five semiannual loan repayments		12.50%
Maximum borrowing capacity		$ 30,900		200.0
Expiration date		Aug. 31, 2022
Proceeds from line of credit		$ 21,000		135.7
Available borrowing capacity		$ 9,900		¥ 62.5
Number of lithography tools to be purchased | Tool		2
Finance Leases [Member]
Long Term Debt Maturing In Year One [Abstract]
Next 12 months		$ 7,119
Long-term Debt [Abstract]
Months 13 - 24		6,487
Months 25 - 36		6,585
Months 37 - 48		19,623
Months 49 - 60		0
Long-term debt		$ 32,695
Interest rate at balance sheet date	[3]
Maturity date	[3]
Periodic payment amount	[3]
Periodic payment frequency		Monthly
Loan collateral (carrying amount)	[4]	$ 41,537
Finance lease contract term					5 years
Finance lease amount					$ 7,200	$ 35,500
Short-term obligation						$ 3,500
Amended and Restated Credit Agreement [Member]
Long-term Debt [Abstract]
Maximum borrowing capacity		100,000
Amount outstanding		$ 0
Term of loan		5 years
Current borrowing capacity		$ 50,000
Cash limit for dividends, distributions and redemption on equity		$ 50,000
Effective interest rate		1.09%		1.09%

[1] First five loan repayments will each be for 7.5 percent of the approved 200 million RMB loan principal; last five installments will each be for 12.5 percent of the original approved loan amount.

[2] Semiannual repayments commence in March 2022.

[3] See Note 8 for interest rates on lease liabilities, maturity dates, and periodic payment amounts.

[4] Represents the carrying amount at the balance sheet date of the related right-of-use assets, in which the lessors have secured interests.