LEASES - Right-of-use lease assets and lease liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Right-of-use lease assets and lease liabilities
Operating right-of-use assets, net	$ 23,795	$ 8,358
Current portion of operating lease liabilities	5,356	1,959
Long-term operating lease liabilities	18,613	6,554
Total operating lease liabilities	23,969	8,513
Finance lease right-of-use assets, net	57	60
Current portion of finance lease liabilities	23	24
Long-term finance lease liabilities	37	39
Total finance lease liabilities	$ 60	$ 63