GOODWILL AND INTANGIBLE ASSETS - Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2019	Sep. 30, 2018
Intangible Assets
Gross Carrying Amount	$ 79,900	$ 79,700
Accumulated Amortization	10,807	6,493
Net	$ 69,093	73,207
Developed technology
Intangible Assets
Estimated Useful Lives	15 years
Gross Carrying Amount	$ 70,200	70,000
Accumulated Amortization	9,089	5,589
Net	$ 61,111	64,411
Trade name
Intangible Assets
Estimated Useful Lives	20 years
Gross Carrying Amount	$ 5,700	5,700
Accumulated Amortization	451	237
Net	$ 5,249	5,463
Customer relationships
Intangible Assets
Estimated Useful Lives	5 years
Gross Carrying Amount	$ 4,000	4,000
Accumulated Amortization	1,267	667
Net	$ 2,733	$ 3,333