GOODWILL AND INTANGIBLE ASSETS Schedule of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Beginning balance	$ 309,505	$ 303,270
Acquisitions	0	0
Impairment	0	0
Ending balance	309,505	303,270
Consumer
Goodwill [Roll Forward]
Beginning balance	87,145	87,145
Acquisitions	0	0
Impairment	0	0
Ending balance	87,145	87,145
Commercial
Goodwill [Roll Forward]
Beginning balance	222,360	216,125
Acquisitions	0	0
Impairment	0	0
Ending balance	222,360	216,125
Corporate Services/Other
Goodwill [Roll Forward]
Beginning balance	0	0
Acquisitions	0	0
Impairment	0	0
Ending balance	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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