CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
INTEREST INCOME
Loans receivable	$ 138,549	$ 141,061	$ 280,695	$ 278,126
Mortgage-backed securities	14,341	19,343	29,953	38,535
Investment securities and cash equivalents	6,728	7,178	13,794	13,543
Interest income	159,618	167,582	324,442	330,204
INTEREST EXPENSE
Customer accounts	28,638	29,666	60,119	56,245
FHLB advances	13,368	17,846	27,026	34,737
Interest expense	42,006	47,512	87,145	90,982
Net interest income	117,612	120,070	237,297	239,222
Provision (release) for credit losses	6,200	750	5,200	250
Net interest income after provision (release)	111,412	119,320	232,097	238,972
OTHER INCOME
Gain (loss) on sale of investment securities	15,028	0	15,028	(9)
Prepayment penalty on long-term debt	(13,809)	0	(13,809)	0
Loan fee income	3,048	667	4,852	1,637
Other income	5,875	6,257	44,187	18,062
Other income, total	16,241	12,810	62,617	31,819
OTHER EXPENSE
Compensation and benefits	38,617	32,774	75,248	66,657
Occupancy	10,913	9,830	21,048	19,098
FDIC insurance premiums	2,470	1,978	4,940	4,840
Product delivery	3,897	3,545	8,164	7,566
Information technology	11,501	8,755	28,608	17,795
Other expense	12,035	11,085	24,061	23,683
Other expense, total	79,433	67,967	162,069	139,639
Gain (loss) on real estate owned, net	31	808	(855)	1,128
Income before income taxes	48,251	64,971	131,790	132,280
Income tax expense	10,301	13,873	28,137	28,240
NET INCOME	$ 37,950	$ 51,098	$ 103,653	$ 104,040
PER SHARE DATA
Basic earnings per share (in dollars per share)	$ 0.49	$ 0.63	$ 1.33	$ 1.28
Diluted earnings per share (in dollars per share)	0.49	0.63	1.33	1.28
Dividends paid on common stock per share (in dollars per share)	$ 0.22	$ 0.20	$ 0.43	$ 0.38
Basic weighted average number of shares outstanding (in shares)	76,987,532	80,968,050	77,737,977	81,384,456
Diluted weighted average number of shares outstanding (in shares)	77,007,118	80,990,126	77,776,304	81,415,697
Deposit Account
OTHER INCOME
Deposit fee income	$ 6,099	$ 5,886	$ 12,359	$ 12,129