PARENT COMPANY FINANCIAL STATEMENTS - Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
ASSETS
Cash and cash equivalents	$ 388,038	$ 314,019
Investment securities held to maturity, at cost	41,682	56,669
Other assets	295,324	212,276
Total assets	6,747,410	6,690,650	$ 6,092,074
LIABILITIES
Subordinated debentures, net of issuance costs	20,000	73,980
Other liabilities	200,205	210,961
Total liabilities	6,102,270	5,818,766
STOCKHOLDERS' EQUITY
Additional paid-in capital	617,403	604,484
Retained earnings	245,394	259,189
Accumulated other comprehensive income (loss)	(213,080)	7,599
Treasury stock, at cost	(4,835)	(860)
Total equity attributable to parent	645,170	870,729
Noncontrolling interest	(30)	1,155
Total stockholders' equity	645,140	871,884	$ 847,308	$ 843,958
Total liabilities and stockholders' equity	6,747,410	6,690,650
Meta Financial
ASSETS
Cash and cash equivalents	13,117	3,296
Investment securities held to maturity, at cost	8,003	4,623
Investment in subsidiaries	665,172	956,584
Other assets	928	278
Total assets	687,220	964,781
LIABILITIES
Subordinated debentures, net of issuance costs	33,661	87,641
Other liabilities	8,419	5,256
Total liabilities	42,080	92,897
STOCKHOLDERS' EQUITY
Common stock	288	317
Additional paid-in capital	617,403	604,484
Retained earnings	245,394	259,189
Accumulated other comprehensive income (loss)	(213,080)	7,599
Treasury stock, at cost	(4,835)	(860)
Total equity attributable to parent	645,170	870,729
Noncontrolling interest	(30)	1,155
Total stockholders' equity	645,140	871,884
Total liabilities and stockholders' equity	$ 687,220	$ 964,781