GOODWILL AND INTANGIBLE ASSETS - Schedule of Goodwill (Details) - USD ($)	9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Goodwill [Roll Forward]
Beginning balance	$ 309,505,000	$ 303,270,000
Acquisitions	0	0
Measurement Period Adjustment		4,671,000
Impairment	0	0
Ending balance	309,505,000	307,941,000
Goodwill, accumulated impairment	0
Consumer
Goodwill [Roll Forward]
Beginning balance	87,145,000	87,145,000
Acquisitions	0	0
Measurement Period Adjustment		0
Impairment	0	0
Ending balance	87,145,000	87,145,000
Commercial
Goodwill [Roll Forward]
Beginning balance	222,360,000	216,125,000
Acquisitions	0	0
Measurement Period Adjustment		4,671,000
Impairment	0	0
Ending balance	222,360,000	220,796,000
Corporate Services/Other
Goodwill [Roll Forward]
Beginning balance	0	0
Acquisitions	0	0
Measurement Period Adjustment		0
Impairment	0	0
Ending balance	$ 0	$ 0