LONG-TERM DEBT (Details) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended	6 Months Ended
	May 31, 2019 USD ($)	Jun. 05, 2019 USD ($)	Apr. 30, 2016 USD ($) shares $ / shares	Jan. 31, 2015 USD ($) shares $ / shares	Apr. 28, 2019 USD ($)	Apr. 28, 2019 USD ($)	Oct. 31, 2018 USD ($)	Mar. 31, 2011 USD ($)
Long-term debt [Abstract]
Long term debt					$ 36,426	$ 36,426	$ 57,453
Current portion					(505)	(505)	(57,453)
Long-term debt noncurrent					$ 35,921	35,921	0
Cash limit for dividends, distributions and redemption on equity						$ 100,000
Short Term Debt Due in February 2019 [Member]
Long-term debt [Abstract]
Interest rate percentage					4.90%	4.90%
Maturity date of debt						Feb. 28, 2019
Repayments of debt						$ 3,700
Term of loan						90 days
Project Loan [Member]
Long-term debt [Abstract]
Interest rate percentage					4.90%	4.90%
Maximum borrowing capacity					$ 50,000	$ 50,000
Project Loan [Member] | Subsequent Event [Member]
Long-term debt [Abstract]
Proceeds from credit facility		$ 9,700
Project Loan Due December 2025 [Member]
Long-term debt [Abstract]
Long term debt					11,400	$ 11,400	0
Maturity date of debt						Dec. 31, 2025
Date of first required payment						Jun. 30, 2023
Proceeds from credit facility					11,400
Project Loan Due December 2022 [Member]
Long-term debt [Abstract]
Long term debt					14,932	$ 14,932	0
Maturity date of debt						Dec. 31, 2022
Date of first required payment						Jun. 30, 2020
Working Capital Loan due January 2022 [Member]
Long-term debt [Abstract]
Long term debt					$ 10,094	$ 10,094	0
Interest rate percentage					5.00%	5.00%
Basis spread on variable rate						0.6775%
Maturity date of debt						Jan. 31, 2022
Date of first required payment						May 31, 2019
Maximum borrowing capacity					$ 25,000	$ 25,000
Proceeds from credit facility						13,800
Working Capital Loan due January 2022 [Member] | Subsequent Event [Member]
Long-term debt [Abstract]
Amount outstanding under credit facility	$ 1,900
Repayments of debt	$ 100
3.25% Convertible Senior Notes Matured April 2019 [Member]
Long-term debt [Abstract]
Long term debt					0	0	$ 57,453
Face amount of debt					$ 57,500	$ 57,500
Interest rate percentage					3.25%	3.25%
Maturity date of debt						Apr. 01, 2019
Number of shares each note is convertible to (in shares) | shares				96
Face amount of each note converted				$ 1
Conversion price per share (in dollars per share) | $ / shares				$ 10.37
Repayments of debt						$ 57,500
Amended and Restated Credit Agreement [Member]
Long-term debt [Abstract]
Maturity date of debt						Sep. 30, 2023
Current borrowing capacity					$ 50,000	$ 50,000
Maximum borrowing capacity					100,000	100,000
Amount outstanding under credit facility					0	0
Available borrowing capacity					$ 50,000	$ 50,000
Effective interest rate					2.50%	2.50%
3.25% Convertible Senior Notes due in April 2016 [Member]
Long-term debt [Abstract]
Face amount of debt								$ 57,500
Interest rate percentage			3.25%
Maturity date of debt			Apr. 01, 2016
Number of shares each note is convertible to (in shares) | shares			96
Face amount of each note converted			$ 1
Conversion price per share (in dollars per share) | $ / shares			$ 10.37