REVENUE RECOGNITION - Contract Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Contract assets, current	$ 17,305	$ 18,355	$ 6,223	$ 7,037
Contract assets, non-current	7,216	5,579	10,741	4,218
Contract liabilities (deferred revenue), current	18,330	17,360	12,647	21,350
Contract liabilities (deferred revenue), non-current	$ 1,051	$ 957	$ 1,236	$ 1,775