Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Sep. 30, 2017	Sep. 30, 2016
Interest income:
Loans receivable	$ 43,043	$ 189,869	$ 164,849	$ 152,110
Securities available for sale	5,074	25,338	17,163	15,145
Securities held to maturity	382	7,147	68	0
Federal funds and interest earning deposits	103	1,175	308	205
Federal Home Loan Bank stock dividends	567	2,761	1,838	1,517
Total interest income	49,169	226,290	184,226	168,977
Interest expense:
Deposits	7,631	39,523	25,581	24,062
Borrowings	4,609	22,733	18,865	19,900
Total interest expense	12,240	62,256	44,446	43,962
Net interest income	36,929	164,034	139,780	125,015
Provision for loan losses	3,400	6,677	6,426	417
Net interest income after provision for loan losses	33,529	157,357	133,354	124,598
Non-interest income:
Bank-owned life insurance	1,089	5,208	4,936	4,370
Title insurance fees	1,017	4,297	4,163	4,198
Gain (loss) on securities transactions, net	(60)	116	(1,689)	355
Gain (loss) on sale of loans	0	618	(380)	655
(Loss) gain on sale of real estate owned	0	(56)	233	(441)
Other non-interest income	1,162	4,999	4,264	4,548
Total non-interest income	4,733	21,688	17,172	18,927
Non-interest expense:
Compensation and employee benefits	15,624	69,907	62,993	58,115
Occupancy	3,382	14,547	13,315	12,798
Federal deposit insurance premiums	414	1,893	1,652	2,381
Advertising	1,408	4,137	4,078	2,938
Professional fees	398	1,432	1,354	1,061
Data processing	595	2,600	2,244	2,143
Charitable contribution to foundation	0	34,767	3,603	347
Other non-interest expense	3,780	16,103	14,207	13,986
Total non-interest expense	25,601	145,386	103,446	93,769
Income before income tax expense	12,661	33,659	47,080	49,756
Income tax expense	8,983	10,923	16,008	16,803
Net income	3,678	$ 22,736	31,072	32,953
Basic and diluted earnings per share (in dollars per share)		$ 0.20
Weighted average shares outstanding (in shares)		111,395,723
Deposit Account
Non-interest income:
Non-interest income	960	$ 3,987	3,669	3,271
Bank Servicing
Non-interest income:
Non-interest income	$ 565	$ 2,519	$ 1,976	$ 1,971