Customer Accounts (Tables)

12 Months Ended

Sep. 30, 2023

Banking and Thrift, Interest [Abstract]

Schedule of Deposit Liabilities

The following tables provide the composition of the Company's customer accounts, including time deposits.

	September 30, 2023						September 30, 2022
	Deposit Account Balance		As a % of Total Deposits		Weighted Average Rate		Deposit Account Balance		As a % of Total Deposits		Weighted Average Rate
($ in thousands)
Non-interest checking	$	2,706,448	16.8	%	—	%	$	3,266,734	20.4	%	—	%
Interest checking	3,882,715		24.2		2.28		3,497,795		21.8		0.90
Savings	817,547		5.1		0.21		1,059,093		6.6		0.13
Money market	3,358,603		20.9		1.48		4,867,905		30.4		0.49
Time deposits	5,305,016		33.0		3.77		3,338,043		20.8		0.74
Total	$	16,070,329	100	%	2.12	%	$	16,029,570	100	%	0.51	%

Schedule of Time Deposits

Time deposits by rate band are as follows:	September 30, 2023		September 30, 2022
	(In thousands)
Less than 1.00%	$	139,525	$	2,705,212
1.00% to 1.99%	64,262		304,702
2.00% to 2.99%	248,973		327,852
3.00% to 3.99%	3,884,337		277
4.00% to 4.99%	532,153		—
5.00% and higher	435,766		—
	$	5,305,016	$	3,338,043
Time deposits by maturity band are as follows:	September 30, 2023		September 30, 2022
	(In thousands)
Three months or less	$	2,383,793	$	1,007,735
Over 3 through 6 months	1,517,379		966,800
Over 6 through 12 months	732,141		810,680
Over 12 months	671,703		552,828
	$	5,305,016	$	3,338,043

Schedule of Interest Expense on Customer Deposits

Interest expense on customer accounts consisted of the following: 

Year ended September 30,	2023			2022			2021
	(In thousands)
Checking accounts	$	70,396		$	10,086		$	5,545
Savings accounts	1,715			1,377			1,143
Money market accounts	47,485			12,423			8,723
Time deposit accounts	119,255			19,422			27,100
	238,851			43,308			42,511
Less early withdrawal penalties	(1,618)			(267)			(198)
	$	237,233		$	43,041		$	42,313
Weighted average interest rate at end of year	2.12		%	0.51		%	0.23		%
Daily weighted average interest rate during the year	1.84		%	0.34		%	0.35		%