Prudential Bancorp (PBIP) 10-Q 17 May 21 2021 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Mar. 31, 2021	May 07, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity Registrant Name	PRUDENTIAL BANCORP, INC.
Entity Central Index Key	0001578776
Entity File Number	000-55084
Entity Incorporation, State or Country Code	PA
Entity Tax Identification Number	46-2935427
Entity Address, Address Line One	1834 West Oregon Avenue
Entity Address, City or Town	Philadelphia
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19145
City Area Code	215
Local Phone Number	755-1500
Title of 12(b) Security	Common Stock
Trading Symbol	PBIP
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock Shares Outstanding		7,858,818
Amendment Flag	false
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2

CONSOLIDATED STATEMENT OF FINAN

CONSOLIDATED STATEMENT OF FINANCIAL CONDITION - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
ASSETS
Cash and amounts due from depository institutions	$ 2,125	$ 2,781
Interest-bearing deposits	133,104	114,300
Total cash and cash equivalents	135,229	117,081
Certificates of deposit	2,102	2,102
Investment and mortgage-backed securities available for sale at fair value	353,807	420,364
Investment and mortgage-backed securities held to maturity (fair value-March 31, 2021, $23,460; September 30, 2020, $24,330)	22,270	22,860
Equity securities	54	51
Loans receivable-net of allowance for loan losses (March 31, 2021, $8,353; September 30, 2020, $8,303)	620,875	588,300
Accrued interest receivable	4,946	4,699
Office properties and equipment-net	7,017	7,129
Bank owned life insurance (BOLI)	32,812	32,498
Deferred income taxes, net	3,413	3,902
Goodwill	6,102	6,102
Core deposit intangible	291	340
Prepaid expenses and other assets	4,102	5,393
Restricted bank stock	11,012	12,532
TOTAL ASSETS	1,204,032	1,223,353
Deposits:
Non-interest-bearing	32,253	30,002
Interest-bearing	761,492	740,947
Total deposits	793,745	770,949
Advances from Federal Home Loan Bank - short term		25,000
Advances from Federal Home Loan Bank - long term	251,639	260,253
Accrued interest payable	1,898	3,374
Advances from borrowers for taxes and insurance	1,623	2,798
Interest rate swap contracts	14,881	20,960
Accounts payable and accrued expenses	9,988	10,902
Total liabilities	1,073,774	1,094,236
STOCKHOLDERS' EQUITY:
Preferred stock, $.01 par value, 10,000,000 shares authorized; none issued
Common stock, $.01 par value, 40,000,000 shares authorized; 10,819,006 issued and 7,944,002 outstanding at March 31, 2021; 10,819,006 issued and 8,138,675 outstanding at September 30, 2020	108	108
Additional paid-in capital	118,295	118,270
Treasury stock, at cost: 2,875,004 shares at March 31, 2021 and 2,680,331 shares at September 30, 2020	(41,909)	(39,207)
Retained earnings	55,313	52,889
Accumulated other comprehensive (loss) income	(1,549)	(2,943)
Total stockholders' equity	130,258	129,117
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 1,204,032	$ 1,223,353

CONSOLIDATED STATEMENT OF FIN_2

CONSOLIDATED STATEMENT OF FINANCIAL CONDITION (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
CONSOLIDATED STATEMENT OF FINANCIAL CONDITION
Investment and mortgage-backed securities held to maturity, fair value (in dollars)	$ 23,460	$ 24,330
Allowance for loan losses on loans receivable (in dollars)	$ 8,353	$ 8,303
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	10,819,006	10,819,006
Common stock, shares outstanding	7,944,002	8,138,675
Number of treasury share purchased	2,875,004	2,680,331

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
INTEREST INCOME:
Interest and fees on loans	$ 6,388,000	$ 6,333,000	$ 12,663,000	$ 13,163,000
Interest on mortgage-backed securities	1,428,000	2,563,000	3,044,000	5,356,000
Interest and dividends on investments	1,643,000	1,764,000	3,357,000	3,566,000
Interest on interest-bearing deposits	6,000	350,000	90,000	752,000
Total interest income	9,465,000	11,010,000	19,154,000	22,837,000
INTEREST EXPENSE:
Interest on deposits	1,961,000	2,866,000	4,131,000	5,991,000
Interest on advances from FHLB - short term	14,000	425,000	39,000	965,000
Interest on advances from FHLB - long term	1,765,000	1,931,000	3,576,000	3,750,000
Total interest expense	3,740,000	5,222,000	7,746,000	10,706,000
NET INTEREST INCOME	5,725,000	5,788,000	11,408,000	12,131,000
PROVISION FOR LOAN LOSSES	0	500,000	0	625,000
NET INTEREST INCOME AFTER PROVISION FOR LOAN LOSSES	5,725,000	5,288,000	11,408,000	11,506,000
NON-INTEREST INCOME:
Fees and other service charges	114,000	150,000	253,000	315,000
Gain on sale of mortgage-backed securities available for sale		2,364,000		2,682,000
Gain (loss) on equity securities, net	(7,000)	(39,000)	3,000	(58,000)
Gain on sale of loans	18,000	239,000	58,000	265,000
Swap income (loss)	216,000	(333,000)	319,000	(300,000)
Earnings from bank owned life insurance	152,000	164,000	313,000	334,000
Other	82,000	123,000	166,000	262,000
Total non-interest income	575,000	2,668,000	1,112,000	3,500,000
NON-INTEREST EXPENSES:
Salaries and employee benefits	2,529,000	2,624,000	4,945,000	4,922,000
Data processing	221,000	234,000	416,000	426,000
Professional services	382,000	308,000	839,000	712,000
Office occupancy	276,000	218,000	505,000	422,000
Depreciation	108,000	113,000	219,000	268,000
Director compensation	54,000	74,000	107,000	133,000
Federal Deposit Insurance Corporation deposit insurance premiums	220,000	195,000	350,000	376,000
Real estate owned expense		93,000		140,000
Advertising	12,000	53,000	44,000	92,000
Core deposit amortization	23,000	26,000	49,000	56,000
Other	525,000	522,000	974,000	934,000
Total non-interest expenses	4,350,000	4,460,000	8,448,000	8,481,000
INCOME BEFORE INCOME TAXES	1,950,000	3,496,000	4,072,000	6,525,000
INCOME TAXES:
Current	240,000	419,000	402,000	985,000
Deferred (benefit) expense	(5,000)	153,000	119,000	153,000
Total income tax provision	235,000	572,000	521,000	1,138,000
NET INCOME	$ 1,715,000	$ 2,924,000	$ 3,551,000	$ 5,387,000
BASIC EARNINGS PER SHARE	$ 0.22	$ 0.33	$ 0.44	$ 0.61
DILUTED EARNINGS PER SHARE	$ 0.21	$ 0.32	$ 0.44	$ 0.60

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
Net income	$ 1,715	$ 2,924	$ 3,551	$ 5,387
Unrealized holding gain (loss) on available-for-sale securities	(4,874)	4,825	(2,792)	3,652
Tax effect	1,032	(1,013)	586	(767)
Reclassification adjustment for net securities (gains) losses realized in net income		(2,364)		(2,682)
Tax effect	(664)	2,292	(959)	1,811
Unrealized holding gain (loss) on interest rate swaps	3,164	(10,914)	4,559	(8,622)
Tax effect		496		563
Total other comprehensive (loss) income	(1,342)	(6,678)	1,394	(6,045)
Comprehensive income (loss)	$ 373	$ (3,754)	$ 4,945	$ (658)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Treasury Stock	Retained EarningsCumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
BALANCE at Sep. 30, 2019	$ 108	$ 118,384	$ (29,698)	$ (75)	$ 49,625	$ 1,192	$ (75)	$ 139,611
Increase (Decrease) in Stockholders' Equity
Net income					5,387			5,387
Other comprehensive income (loss)						(6,045)		(6,045)
Dividends paid					(5,075)			(5,075)
Purchase of treasury stock			(1,999)					(1,999)
Treasury stock used for employee benefit plans		(787)	703					(84)
Stock option expense		270						270
Restricted shares award expense		256						256
BALANCE at Mar. 31, 2020	108	118,123	(30,994)		49,862	(4,853)		132,246
BALANCE at Dec. 31, 2019	108	118,673	(29,698)		51,391	1,825		142,299
Increase (Decrease) in Stockholders' Equity
Net income					2,924			2,924
Other comprehensive income (loss)						(6,678)		(6,678)
Dividends paid					(4,453)			(4,453)
Purchase of treasury stock			(1,999)					(1,999)
Treasury stock used for employee benefit plans		(787)	703					(84)
Stock option expense		117						117
Restricted shares award expense		120						120
BALANCE at Mar. 31, 2020	108	118,123	(30,994)		49,862	(4,853)		132,246
BALANCE at Sep. 30, 2020	108	118,270	(39,207)		52,889	(2,943)		129,117
Increase (Decrease) in Stockholders' Equity
Net income					3,551			3,551
Other comprehensive income (loss)						1,394		1,394
Dividends paid					(1,127)			(1,127)
Purchase of treasury stock			(2,906)					(2,906)
Treasury stock used for employee benefit plans		(143)	204					61
Stock option expense		84						84
Restricted shares award expense		84						84
BALANCE at Mar. 31, 2021	108	118,295	(41,909)		55,313	(1,549)		130,258
BALANCE at Dec. 31, 2020	108	118,356	(41,167)		54,155	(207)		131,245
Increase (Decrease) in Stockholders' Equity
Net income					1,715			1,715
Other comprehensive income (loss)						(1,342)		(1,342)
Dividends paid					(557)			(557)
Purchase of treasury stock			(946)					(946)
Treasury stock used for employee benefit plans		(143)	204					61
Stock option expense		41						41
Restricted shares award expense		41						41
BALANCE at Mar. 31, 2021	$ 108	$ 118,295	$ (41,909)		$ 55,313	$ (1,549)		$ 130,258

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parentheticals) - $ / shares	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY
Dividends paid (in dollars per share)	$ 0.07	$ 0.50	$ 0.14	$ 0.57
Purchase of treasury stock	62,500	152,009	209,311	152,009
Treasury stock used for employee benefit plan	14,638	44,587	14,638	44,587

CONSOLIDATED STATEMENTS OF CH_3

CONSOLIDATED STATEMENTS OF CHANGES OF CASH FLOW - USD ($)	6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
OPERATING ACTIVITIES:
Net income	$ 3,551,000	$ 5,387,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	219,000	268,000
Net amortization/accretion of premiums/discounts and other amortization	(372,000)	(877,000)
Earnings on BOLI	(313,000)	(334,000)
Provision for loan losses	0	625,000
Accretion of deferred loan fees and costs	(70,000)	(35,000)
(Gain) loss on sale of investment and mortgage-backed securities		(2,682,000)
Gain on sale of loans	(58,000)	(265,000)
Proceeds from the sale of loans	3,820,000	20,713,000
Originations of loans held for sale	(3,762,000)	(6,186,000)
Share-based compensation expense	168,000	526,000
Holding (gains) losses on equity securities	(3,000)	58,000
Holding losses (gains) on equity securities	(3,000)	58,000
Deferred income tax benefit	119,000	(153,000)
Changes in assets and liabilities which used cash:
Accrued interest receivable	(247,000)	137,000
Accrued interest payable	(1,476,000)	(1,481,000)
Other, net	399,000	106,000
Net cash provided by operating activities	1,975,000	15,807,000
INVESTING ACTIVITIES:
Purchase of investment and mortgage-backed securities available for sale	(19,196,000)	(130,257,000)
Purchase of investment and mortgage-backed securities held to maturity		(2,500,000)
Loans originated or acquired	(144,832,000)	(55,211,000)
Principal collected on loans	112,528,000	53,750,000
Principal payments received on investment and mortgage-backed securities:
Held-to-maturity	544,000	42,179,000
Available-for-sale	81,683,000	65,441,000
Proceeds from sale of investment and mortgage-backed securities		81,953,000
Proceeds from redemption of FHLB stock	2,541,000	5,489,000
Purchase of FHLB stock	(1,021,000)	(4,635,000)
Purchases of equipment	(107,000)	(233,000)
Net cash provided by investing activities	32,140,000	55,976,000
FINANCING ACTIVITIES:
Net increase (decrease) in demand deposits, NOW accounts, and savings accounts	(9,516,000)	45,814,000
Net (decrease) increase in certificates of deposit	32,311,000	(59,774,000)
Net (decrease) increase in FHLB short-term advances	(25,000,000)	(10,000,000)
Repayment of FHLB advances - long term	(8,615,000)	(12,280,000)
Increase in advances from borrowers for taxes and insurance	(1,175,000)	335,000
Cash dividends paid	(1,127,000)	(5,075,000)
Treasury stock used for employee benefit plans	61,000	(84,000)
Purchase of treasury stock	(2,906,000)	(1,999,000)
Net cash used in financing activities	(15,967,000)	(43,063,000)
NET INCREASE IN CASH AND CASH EQUIVALENTS	18,148,000	28,720,000
CASH AND CASH EQUIVALENTS-Beginning of period	117,081,000	47,968,000
CASH AND CASH EQUIVALENTS-End of period	135,229,000	76,688,000
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Interest on deposits and advances from Federal Home Loan Bank	9,222,000	12,187,000
Income taxes paid	$ 60,000	1,195,000
SUPPLEMENTAL DISCLOSURES OF NONCASH ITEMS
Loans transferred to other real estate owned		183,000
Lease adoption:
Right of use lease asset		1,415,000
Lease liability		$ 1,536,000

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
	Mar. 31, 2021
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	1. SIGNIFICANT ACCOUNTING POLICIES Prudential Bancorp, Inc. (the “Company”) is a Pennsylvania corporation and the parent holding company for Prudential Bank (the “Bank”). The Company is a registered bank holding company. The Bank is a community-oriented, Pennsylvania-chartered savings bank headquartered in South Philadelphia. The banking office network currently consists of the headquarters and main office (which includes a branch office), an administrative office, and nine additional full-service branch offices. Eight of the branch offices are located in Philadelphia (Philadelphia County), one is in Drexel Hill, Delaware County, and one is in Huntingdon Valley, Montgomery County (both Pennsylvania counties). The Bank maintains ATMs at all 10 of the banking offices. The Bank also provides on-line and mobile banking services. The Bank is subject to regulation by the Pennsylvania Department of Banking and Securities (the “Department”), as its chartering authority and primary regulator, and by the Federal Deposit Insurance Corporation (the “FDIC”), which insures the Bank’s deposits up to applicable limits. As a bank holding company, the Company is subject to the regulation of the Board of Governors of the Federal Reserve System. Basis of presentation – Use of Estimates in the Preparation of Financial Statements — Recent Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments Update for SEC filers that are eligible to be smaller reporting companies, non-SEC filers, and all other companies to fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We expect to recognize a one-time cumulative effect adjustment to the allowance for loan losses as of the beginning of the first reporting period in which the new standard is effective, but cannot yet determine the magnitude of any such one-time adjustment or the overall impact of the new guidance on the consolidated financial statements. In May 2019, the FASB issued ASU 2019-05, Financial Instruments – Credit Losses, Topic 326, which allows entities to irrevocably elect the fair value option for certain financial assets previously measured at amortized cost upon adoption of the new credit losses standard. To be eligible for the transition election, the existing financial asset must otherwise be both within the scope of the new credit losses standard and eligible for the applying the fair value option in ASC 825-10-3. The election must be applied on an instrument-by-instrument basis and is not available for either available-for-sale or held-to-maturity debt securities. For entities that elect the fair value option, the difference between the carrying amount and the fair value of the financial asset would be recognized through a cumulative-effect adjustment to opening retained earnings as of the date an entity adopted ASU 2016-13. Changes in fair value of that financial asset would subsequently be reported in current earnings. For entities that have not yet adopted ASU 2016-13, the effective dates and transition requirements are the same as those in ASU 2016-13. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and or results of operations. In November 2019, the FASB issued ASU 2019-10, Financial Instruments ‒ Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) In January 2020, the FASB issued ASU 2020-4, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, March 2020, to provide temporary optional expedients and exceptions to the U.S. GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens of the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates, such as Secured Overnight Financing Rate. Entities can elect not to apply certain modification accounting requirements to contracts affected by what the guidance calls reference rate reform, if certain criteria are met. An entity that makes this election would not have to remeasure the contracts at the modification date or reassess a previous accounting determination. Also, entities can elect various optional expedients that would allow them to continue applying hedge accounting for hedging relationships affected by reference rate reform, if certain criteria are met, and can make a one-time election to sell and/or reclassify held-to-maturity debt securities that reference an interest rate affected by reference rate reform. The amendments in this ASU are effective for all entities upon issuance through March 31, 2022. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and/or results of operations. ​ In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848) certain hedging relationships existing as of December 31, 2022, that apply certain optional expedients in which the accounting effects are recorded through the end of the hedging relationship. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and/or results of operations.

EARNINGS PER SHARE

EARNINGS PER SHARE	6 Months Ended
	Mar. 31, 2021
EARNINGS PER SHARE
EARNINGS PER SHARE	2. EARNINGS PER SHARE Basic earnings per common share is computed by dividing net income available to common stockholders by the weighted average number of shares of common stock issued, net of any treasury shares and unearned restricted share awards, during the period. Diluted earnings per share is calculated by dividing net income available to common stockholders by the weighted average number of shares of common stock outstanding, net of any treasury shares, after consideration of the potential dilutive effect of common stock equivalents (CSEs), based upon the treasury stock method using an average market price for the period. The calculated basic and diluted earnings per share are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ ​ 2021 ​ 2020 ​ ​ ​ (Dollars in Thousands Except Per Share Data) ​ ​ Basic Diluted Basic Diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 1,715 ​ $ 1,715 ​ $ 2,924 ​ $ 2,924 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding ​ 7,975,683 ​ 7,975,683 ​ 8,884,760 ​ 8,884,760 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of CSEs ​ — ​ 14,671 ​ — ​ 117,342 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Adjusted weighted average common shares used in earnings per share computation ​ 7,975,683 ​ 7,990,354 ​ 8,884,760 ​ 9,002,102 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per share ​ $ 0.22 ​ $ 0.21 ​ $ 0.33 ​ $ 0.32 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, ​ ​ 2021 ​ 2020 ​ ​ (Dollars in Thousands, Except Share and Per Share Data) ​ Basic Diluted Basic Diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 3,551 ​ $ 3,551 ​ $ 5,387 ​ $ 5,387 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding ​ 8,040,907 ​ 8,040,907 ​ 8,885,972 ​ 8,885,972 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of CSEs ​ — ​ 4,512 ​ — ​ 133,815 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Adjusted weighted average common shares used in earnings per share computation ​ 8,040,907 ​ 8,045,419 ​ 8,885,972 ​ 9,019,787 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per share ​ $ 0.44 ​ $ 0.44 ​ $ 0.61 ​ $ 0.60 ​ As of March 31, 2021 and 2020, there were 267,728 and 528,004 shares of common stock, respectively, subject to options with exercise prices less than the then current market and which were included in the computation of diluted earnings per share. At March 31, 2021 and 2020, there were 249,030 and 265,030 shares of common stock, respectively, subject to options that had exercise prices greater than the then current market value and were considered anti-dilutive at such dates.

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	6 Months Ended
	Mar. 31, 2021
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	3. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) The following tables present the changes in accumulated other comprehensive income (loss) by component, net of tax, for the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ Three Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ ​ ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ ​ securities (a) (a) income (loss) securities (a) (a) income (loss) ​ Beginning balance, January 1 ​ $ 12,221 ​ $ (12,428) ​ $ (207) ​ $ 6,920 ​ $ (5,096) ​ $ 1,824 ​ Other comprehensive (loss) income before reclassification ​ (3,842) ​ 2,500 ​ (1,342) ​ 3,812 ​ (8,621) ​ (4,809) ​ Total other comprehensive income (loss) ​ 8,379 ​ (9,928) ​ (1,549) ​ 10,732 ​ (13,717) ​ (2,985) ​ Reclassification for net gains recorded in net income ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,868) ​ ​ — ​ ​ (1,868) ​ Ending balance, March 31 ​ $ 8,379 ​ $ (9,928) ​ $ (1,549) ​ $ 8,864 ​ $ (13,717) ​ $ (4,853) ​ (a) All amounts are net of tax. Amounts in parentheses indicate debits. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ Six Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ securities (a) (a) income (loss) securities (a) (a) income (loss) Beginning balance, October 1 ​ $ 10,585 ​ $ (13,528) ​ $ (2,943) ​ $ 8,098 ​ $ (6,906) ​ $ 1,192 Other comprehensive (loss) income before reclassification ​ (2,206) ​ 3,600 ​ 1,394 ​ 2,885 ​ (6,811) ​ (3,926) Total other comprehensive income (loss) ​ 8,379 ​ (9,928) ​ (1,549) ​ 10,983 ​ (13,717) ​ (2,734) Reclassification for net gains recorded in net income ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,119) ​ ​ — ​ ​ (2,119) Ending balance, March 31 ​ $ 8,379 ​ $ (9,928) ​ $ (1,549) ​ $ 8,864 ​ $ (13,717) ​ $ (4,853) ​ (a) All amounts are net of tax. Amounts in parentheses indicate debits.

INVESTMENT AND MORTGAGE-BACKED

INVESTMENT AND MORTGAGE-BACKED SECURITIES	6 Months Ended
	Mar. 31, 2021
INVESTMENT AND MORTGAGE-BACKED SECURITIES
INVESTMENT AND MORTGAGE-BACKED SECURITIES	4. INVESTMENT AND MORTGAGE-BACKED SECURITIES The amortized cost and fair value of investment and mortgage-backed securities, with gross unrealized gains and losses, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency obligations ​ $ 10,811 ​ $ 82 ​ $ — ​ $ 10,893 State and political subdivisions ​ 77,437 ​ 2,560 ​ (646) ​ 79,351 Mortgage-backed securities - U.S. government agencies ​ ​ 174,243 ​ ​ 6,387 ​ ​ (929) ​ ​ 179,701 Corporate debt securities ​ 80,709 ​ 3,337 ​ (184) ​ 83,862 Total debt securities available for sale ​ $ 343,200 ​ $ 12,366 ​ $ (1,759) ​ $ 353,807 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held to Maturity: ​ ​ ​ ​ U.S. government and agency obligations ​ $ 1,000 ​ $ 185 ​ $ — ​ $ 1,185 State and political subdivisions ​ 18,022 ​ 738 ​ — ​ 18,760 Mortgage-backed securities - U.S. government agencies ​ 3,248 ​ 267 ​ — ​ 3,515 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities held to maturity ​ $ 22,270 ​ $ 1,190 ​ $ — ​ $ 23,460 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency obligations ​ $ 22,241 ​ $ 153 ​ $ — ​ $ 22,394 State and political subdivisions ​ ​ 79,099 ​ 1,940 ​ (1,418) ​ 79,621 Mortgage-backed securities - U.S. government agencies ​ 226,863 ​ ​ 9,774 ​ ​ (71) ​ ​ 236,566 Corporate debt securities ​ 78,764 ​ 3,564 ​ (545) ​ 81,783 Total debt securities ​ $ 406,967 ​ $ 15,431 ​ $ (2,034) ​ $ 420,364 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held to Maturity: ​ ​ ​ ​ U.S. government and agency obligations ​ $ 1,000 ​ $ 236 ​ $ — ​ $ 1,236 State and political subdivisions ​ 18,076 ​ 925 ​ — ​ 19,001 Mortgage-backed securities - U.S. government agencies ​ 3,784 ​ 309 ​ — ​ 4,093 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities held to maturity ​ $ 22,860 ​ $ 1,470 ​ $ — ​ $ 24,330 ​ The Company recognized a holding loss on equity securities of $7,000 for the three months ended March 31, 2021, and a holding gain on equity securities of $3,000 for the six months ended March 31, 2021 and holding losses on equity securities of $39,000 and $58,000, respectively, during the three and six months ended March 31, 2020. ​ As of March 31, 2021, the Bank maintained $151.5 million of securities in a safekeeping account at the FHLB of Pittsburgh available to be used for collateral and convenience. As of March 31, 2021, the Bank was only required to hold $39.0 million as specific collateral for its borrowings from the FHLB of Pittsburgh; therefore the $112.5 million of excess securities as of such date were not restricted and could be sold or transferred if needed. The following table shows the gross unrealized losses and related fair values of the Company’s investment and mortgage-backed securities, aggregated by investment category and length of time that individual securities had been in a continuous loss position as of March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less than 12 months ​ More than 12 months ​ Total ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ Fair ​ Unrealized ​ Fair ​ Unrealized ​ Fair ​ Losses Value Losses Value Losses Value ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State and political subdivisions ​ $ (136) ​ $ 10,686 ​ $ (510) ​ $ 6,838 ​ $ (646) ​ $ 17,524 Mortgage-backed securities -U.S. government agencies ​ (929) ​ 25,777 ​ — ​ — ​ (929) ​ 25,777 Corporate debt securities ​ (184) ​ 11,816 ​ — ​ — ​ (184) ​ 11,816 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities available for sale ​ $ (1,249) ​ $ 48,279 ​ $ (510) ​ $ 6,838 ​ $ (1,759) ​ $ 55,117 ​ The following table shows the gross unrealized losses and related fair values of the Company’s investment and mortgage-backed securities, aggregated by investment category and length of time that individual securities had been in a continuous loss position as of September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less than 12 months ​ More than 12 months ​ Total ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Unrealized Fair Unrealized Fair Unrealized Fair ​ ​ Losses ​ Value ​ Losses ​ Value ​ Losses ​ Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ State and political subdivisions ​ $ (126) ​ $ 10,735 ​ $ (1,292) ​ $ 24,510 ​ $ (1,418) ​ $ 35,245 Mortgage-backed securities - US government agencies ​ (66) ​ 10,025 ​ (5) ​ 584 ​ (71) ​ 10,609 Corporate debt securities ​ (545) ​ 16,472 ​ — ​ — ​ (545) ​ 16,472 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities available for sale ​ $ (737) ​ $ 37,232 ​ $ (1,297) ​ $ 25,094 ​ $ (2,034) ​ $ 62,326 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Management evaluates securities for other-than-temporary impairment (“OTTI”) at least once each quarter, and more frequently when economic or market concerns warrant such evaluation. The evaluation is based upon factors such as the creditworthiness of the issuers/guarantors, the underlying collateral, if applicable, and the continuing performance of the securities. Management also evaluates other facts and circumstances that may be indicative of an OTTI condition. This includes, but is not limited to, an evaluation of the type of security, the length of time and extent to which the fair value of the security has been less than cost, and the near-term prospects of the issuer. The Company assesses whether a credit loss exists with respect to a security by considering whether (1) the Company has the intent to sell the security, (2) it is more likely than not that it will be required to sell the security before recovery has occurred, or (3) it does not expect to recover the entire amortized cost basis of the security. The Company bifurcates the OTTI impact on impaired securities where impairment in value is deemed to be other than temporary between the component representing credit loss and the component representing loss related to other factors. The portion of the fair value decline attributable to credit loss must be recognized through a charge to earnings. The credit component is determined by comparing the present value of the cash flows expected to be collected, discounted at the rate in effect before recognizing any OTTI, with the amortized cost basis of the debt security. The Company uses the cash flows expected to be realized from the security, which includes assumptions about interest rates, timing and severity of defaults, estimates of potential recoveries, the cash flow distribution from the security and other factors, then applies a discount rate equal to the effective yield of the security. The difference between the present value of the expected cash flows and the amortized book value is considered a credit loss. The fair value of the security is determined using the same expected cash flows; the discount rate is a rate the Company determines from open market and other sources as appropriate for the particular security. The difference between the fair value and the security’s remaining amortized cost is recognized in other comprehensive income (loss). For both the three and six months ended March 31, 2021 and 2020, the Company did not record any credit losses on investment securities through earnings. Mortgage-Backed Securities – Corporate Debt Securities State and political subdivisions The amortized cost and fair value of debt securities, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. The maturity table below excludes mortgage-backed securities because the contractual maturities of such securities are not indicative of actual maturities due to significant prepayments. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Held to Maturity ​ Available for Sale ​ Amortized Fair Amortized Fair ​ ​ Cost ​ Value ​ Cost ​ Value ​ ​ (Dollars in Thousands) Due after one through five years ​ $ 5,693 ​ $ 6,085 ​ $ 31,190 ​ $ 32,832 Due after five through ten years ​ 9,284 ​ 9,594 ​ 50,705 ​ 52,297 Due after ten years ​ 4,045 ​ 4,266 ​ 87,062 ​ 88,977 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 19,022 ​ $ 19,945 ​ $ 168,957 ​ $ 174,106 ​ During the three and six month period ended March 31, 2021, the Company sold no securities. During the three month period ended March 31, 2020, the Company sold securities with an aggregate amortized cost of $44.6 million, for a recognized aggregate gain of $2.4 million (pre-tax). For the six month period ended March 31, 2020, the Company sold securities with an aggregate amortized cost of $62.1 million, for a recognized gain of $2.7 million (pre-tax).

LOANS RECEIVABLE

LOANS RECEIVABLE	6 Months Ended
	Mar. 31, 2021
LOANS RECEIVABLE
LOANS RECEIVABLE	5. LOANS RECEIVABLE Loans receivable consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ 2021 2020 ​ ​ ​ (Dollars in Thousands) ​ One-to-four family residential ​ $ 210,569 ​ $ 233,872 ​ Multi-family residential ​ 52,657 ​ 31,100 ​ Commercial real estate ​ 149,385 ​ 139,943 ​ Construction and land development ​ 264,618 ​ 260,648 ​ Loans to financial institutions ​ — ​ 6,000 ​ Commercial business ​ 41,882 ​ 12,916 ​ Leases ​ 117 ​ 176 ​ Consumer ​ 515 ​ 604 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total loans ​ 719,743 ​ 685,259 ​ ​ ​ ​ ​ ​ ​ ​ ​ Undisbursed portion of loans-in-process ​ (89,912) ​ (86,862) ​ Deferred loan fees ​ (603) ​ (1,794) ​ Allowance for loan losses ​ (8,353) ​ (8,303) ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loans ​ $ 620,875 ​ $ 588,300 ​ ​ The following table summarizes by loan segment the balance in the allowance for loan losses and the loans individually and collectively evaluated for impairment by loan segment at March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to ​ ​ ​ ​ ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four- ​ Multi-family ​ Commercial ​ Construction and ​ financial ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ family residential ​ residential ​ real estate ​ land development ​ institutions ​ business ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ ​ ​ $ — Collectively evaluated for impairment ​ ​ 1,583 ​ ​ 720 ​ ​ 1,969 ​ ​ 2,710 ​ ​ — ​ ​ 580 ​ ​ 3 ​ ​ 5 ​ ​ 783 ​ ​ 8,353 Total ending allowance balance ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ — ​ $ 580 ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,475 ​ $ — ​ $ 1,328 ​ $ 8,250 ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ $ 13,053 Collectively evaluated for impairment ​ 207,094 ​ 52,657 ​ 148,057 ​ 256,368 ​ — ​ 41,882 ​ 117 ​ 515 ​ ​ ​ ​ 706,690 Total loans ​ $ 210,569 ​ $ 52,657 ​ $ 149,385 ​ $ 264,618 ​ $ — ​ $ 41,882 ​ $ 117 ​ $ 515 ​ ​ ​ ​ $ 719,743 ​ The following table summarizes by loan segment the balance in the allowance for loan losses and the loans individually and collectively evaluated for impairment by loan segment at September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four- ​ Multi-family ​ Commercial ​ Construction and ​ financial ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ family residential residential real estate land development institutions ​ business Leases Consumer ​ Unallocated Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ ​ ​ $ — Collectively evaluated for impairment ​ ​ 1,877 ​ ​ 460 ​ ​ 1,989 ​ ​ 2,888 ​ ​ 89 ​ ​ 194 ​ ​ 3 ​ ​ 6 ​ ​ 797 ​ ​ 8,303 Total ending allowance balance ​ $ 1,877 ​ $ 460 ​ $ 1,989 ​ $ 2,888 ​ $ 89 ​ $ 194 ​ $ 3 ​ $ 6 ​ $ 797 ​ $ 8,303 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,095 ​ $ — ​ $ 1,417 ​ $ 8,525 ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ $ 13,037 Collectively evaluated for impairment ​ 230,777 ​ 31,100 ​ 138,526 ​ 252,123 ​ 6,000 ​ 12,916 ​ 176 ​ 604 ​ ​ ​ ​ 672,222 Total loans ​ $ 233,872 ​ $ 31,100 ​ $ 139,943 ​ $ 260,648 ​ $ 6,000 ​ $ 12,916 ​ $ 176 ​ $ 604 ​ ​ ​ ​ $ 685,259 ​ The loan portfolio is segmented at a level that allows management to monitor both risk and performance. Management evaluates for potential impairment all construction loans, multi-family loans, commercial real estate loans, commercial business loans, loans to financial institutions, leases and all loans and leases more than 90 days delinquent as to principal and/or interest. Loans are considered to be impaired when, based on current information and events, it is probable that the Company will be unable to collect in full the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Once the determination is made that a loan is impaired, the determination of whether a specific allocation of the allowance is necessary is generally measured by comparing the recorded investment in the loan to the fair value of the loan using one of the following three methods: (a) the present value of the expected future cash flows discounted at the loan’s effective interest rate; (b) the loan’s observable market price; or (c) the fair value of the collateral less selling costs. Management primarily utilizes the fair value of collateral method as a practically expedient alternative. On collateral method evaluations, any portion of the loan deemed uncollectible is charged-off against the loan loss allowance. The following table presents impaired loans by class as of March 31, 2021, segregated by those for which a specific allowance was required and those for which no specific allowance was required. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans with ​ ​ ​ ​ ​ ​ ​ ​ Impaired Loans with ​ No Specific ​ ​ ​ ​ ​ ​ Specific Allowance ​ Allowance ​ Total Impaired Loans ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid ​ ​ Recorded ​ Related ​ Recorded ​ Recorded ​ Principal ​ Investment Allowance Investment Investment Balance One-to-four family residential ​ $ — ​ $ — ​ $ 3,475 ​ $ 3,475 ​ $ 3,792 Commercial real estate ​ — ​ — ​ 1,328 ​ 1,328 ​ 1,505 Construction and land development ​ — ​ — ​ 8,250 ​ 8,250 ​ 10,631 Total ​ $ — ​ $ — ​ $ 13,053 ​ $ 13,053 ​ $ 15,928 ​ The following table presents impaired loans by class as of September 30, 2020, segregated by those for which a specific allowance was required and those for which no specific allowance was required. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans with ​ ​ ​ ​ ​ ​ Impaired Loans with ​ No Specific ​ ​ ​ ​ ​ ​ ​ ​ Specific Allowance Allowance Total Impaired Loans ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid ​ ​ Recorded Related Recorded Recorded Principal ​ Investment Allowance Investment Investment Balance One-to-four family residential ​ $ — ​ $ — ​ $ 3,095 ​ $ 3,095 ​ $ 3,482 Commercial real estate ​ — ​ — ​ 1,417 ​ 1,417 ​ 1,600 Construction and land development ​ — ​ — ​ 8,525 ​ 8,525 ​ 10,906 Total ​ $ — ​ $ — ​ $ 13,037 ​ $ 13,037 ​ $ 15,988 ​ The following tables present the average recorded investment in impaired loans and related interest income recognized for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 3,281 ​ $ 4 ​ $ 2 Commercial real estate ​ 1,329 ​ — ​ — Construction and land development ​ 8,338 ​ — ​ — Total impaired loans ​ $ 12,947 ​ $ 4 ​ $ 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 4,195 ​ $ — ​ $ 8 Multi-family residential ​ 74 ​ — ​ — Commercial real estate ​ 1,593 ​ — ​ — Construction and land development ​ 8,726 ​ — ​ — Consumer ​ 16 ​ — ​ — Total impaired loans ​ $ 14,604 ​ $ — ​ $ 8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 3,219 ​ $ 9 ​ $ 2 Commercial real estate ​ 1,358 ​ — ​ — Construction and land development ​ 8,400 ​ — ​ — Consumer ​ — ​ — ​ — Total impaired loans ​ $ 12,977 ​ $ 9 ​ $ 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2020 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 4,195 ​ $ 3 ​ $ 17 Multi-family residential ​ 74 ​ — ​ — Commercial real estate ​ 1,593 ​ — ​ 1 Construction and land development ​ 8,725 ​ — ​ — Commercial business ​ 4 ​ — ​ 1 Consumer ​ 16 ​ — ​ — Total impaired loans ​ $ 14,607 ​ $ 3 ​ $ 19 ​ Federal regulations and our loan policy require that the Company utilize an internal asset classification system as a means of reporting problem and potential problem assets. The Company has incorporated an internal asset classification system, consistent with Federal banking regulations, as a part of its credit monitoring system. Management currently classifies problem and potential problem assets as “special mention”, “substandard,” “doubtful” or “loss” assets. An asset is considered “substandard” if it is inadequately protected by the current net worth and paying capacity of the obligor or of the collateral pledged, if any. “Substandard” assets include those characterized by the “distinct possibility” that the insured institution will sustain “some loss” if the deficiencies are not corrected. Assets classified as “doubtful” have all of the weaknesses inherent in those classified “substandard” with the added characteristic that the weaknesses present make “collection or liquidation in full,” on the basis of currently existing facts, conditions, and values, “highly questionable and improbable.” Assets classified as “loss” are those considered “uncollectible” and of such little value that their continuance as assets without the establishment of a specific loss reserve is not warranted. Assets which do not currently expose the insured institution to sufficient risk to warrant classification in one of the three aforementioned categories but possess weaknesses are required to be designated “special mention.” The following tables present the classes of the loan portfolio in which a formal risk weighting system is utilized summarized by the aggregate “Pass” and the criticized category of “special mention”, and the classified categories of “substandard”, “doubtful” and “loss” within the Company’s risk rating system as applied to the loan portfolio. The Company had no loans classified as “doubtful” or “loss” at either of the dates presented. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ Special ​ ​ ​ ​ ​ ​ ​ ​ ​ Pass Mention Substandard Doubtful Total ​ ​ (Dollars in Thousands) One-to-four residential ​ $ 205,653 ​ $ 1,441 ​ $ 3,475 ​ $ — ​ $ 210,569 Multi-family residential ​ 52,657 ​ — ​ — ​ — ​ 52,657 Commercial real estate ​ 138,307 ​ 9,750 ​ 1,328 ​ — ​ 149,385 Construction and land development ​ 256,368 ​ — ​ 8,250 ​ — ​ 264,618 Commercial business ​ 41,882 ​ — ​ — ​ — ​ 41,882 Total ​ $ 694,867 ​ $ 11,191 ​ $ 13,053 ​ $ — ​ $ 719,111 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ Special ​ ​ ​ ​ ​ ​ ​ Pass Mention Substandard Doubtful Total ​ ​ (Dollars in Thousands) One-to-four residential ​ $ 229,361 ​ $ 1,416 ​ $ 3,095 ​ $ — ​ $ 233,872 Multi-family residential ​ 31,100 ​ — ​ — ​ — ​ 31,100 Commercial real estate ​ 128,527 ​ 9,999 ​ 1,417 ​ — ​ 139,943 Construction and land development ​ 252,123 ​ — ​ 8,525 ​ — ​ 260,648 Loans to financial institutions ​ ​ 6,000 ​ — ​ — ​ — ​ 6,000 Commercial business ​ 12,916 ​ — ​ — ​ — ​ 12,916 Total ​ $ 660,027 ​ $ 11,415 ​ $ 13,037 ​ $ — ​ $ 684,479 ​ The Company evaluates the classification of one-to-four family residential, leases and consumer loans primarily on a pooled basis. If the Company becomes aware that adverse or distressed conditions exist that may affect a particular loan, the loan is downgraded following the above definitions of special mention, substandard, doubtful and loss. The following tables represent loans in which a formal risk rating system is not utilized, but loans are segregated between performing and non-performing based primarily on delinquency status. Non-performing loans that would be included in the table are those loans greater than 90 days past due as to principal and/or interest that do not have a designated risk rating. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Non- ​ ​ ​ Performing ​ Performing ​ Total ​ ​ (Dollars in Thousands) Leases ​ $ 117 ​ $ — ​ $ 117 Consumer ​ 515 ​ — ​ 515 Total ​ $ 632 ​ $ — ​ $ 632 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ Non- ​ ​ ​ Performing ​ Performing ​ Total ​ ​ (Dollars in Thousands) Leases ​ $ 176 ​ $ — ​ $ 176 Consumer ​ 604 ​ — ​ 604 Total ​ $ 780 ​ $ — ​ $ 780 ​ Management further monitors the performance and credit quality of the loan portfolio by analyzing the age of the portfolio as determined by the length of time a recorded payment is due or overdue, as the case may be. The following tables present the loan categories of the loan portfolio summarized by the aging categories of performing loans, delinquent loans and nonaccrual loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 90 Days+ ​ ​ ​ ​ ​ 30 ‑ 89 Days ​ 90 Days + ​ Total ​ Total ​ Non- ​ Past Due ​ ​ Current ​ Past Due ​ Past Due ​ Past Due ​ Loans ​ Accrual ​ and Accruing ​ ​ (Dollars in Thousands) One-to-four family residential $ 206,656 ​ $ 671 ​ $ 3,242 ​ $ 3,913 ​ $ 210,569 ​ $ 3,475 ​ $ — Multi-family residential ​ 52,657 ​ — ​ — ​ — ​ 52,657 ​ — ​ — Commercial real estate ​ 145,673 ​ 2,384 ​ 1,328 ​ 3,712 ​ 149,385 ​ 1,328 ​ — Construction and land development ​ 256,368 ​ — ​ 8,250 ​ 8,250 ​ 264,618 ​ 8,250 ​ — Commercial business ​ 41,882 ​ — ​ — ​ — ​ 41,882 ​ — ​ — Leases ​ 117 ​ — ​ — ​ — ​ 117 ​ — ​ Consumer ​ 458 ​ 57 ​ — ​ 57 ​ 515 ​ — ​ — Total Loans ​ $ 703,811 ​ $ 3,112 ​ $ 12,820 ​ $ 15,932 ​ $ 719,743 ​ $ 13,053 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 90 Days+ ​ ​ ​ ​ ​ 30 ‑ 89 Days ​ 90 Days + ​ Total ​ Total ​ Non- ​ Past Due ​ ​ Current ​ Past Due ​ Past Due ​ Past Due ​ Loans ​ Accrual ​ and Accruing ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 231,196 ​ $ 523 ​ $ 2,153 ​ $ 2,676 ​ $ 233,872 ​ $ 3,095 ​ $ — Multi-family residential ​ 31,100 ​ — ​ — ​ — ​ 31,100 ​ — ​ — Commercial real estate ​ 136,225 ​ 2,301 ​ 1,417 ​ 3,718 ​ 139,943 ​ 1,417 ​ — Construction and land development ​ 252,123 ​ — ​ 8,525 ​ 8,525 ​ 260,648 ​ 8,525 ​ — Commercial business ​ 12,916 ​ — ​ — ​ — ​ 12,916 ​ — ​ — Loans to financial institutions ​ ​ 6,000 ​ — ​ — ​ — ​ 6,000 ​ — ​ — Leases ​ 176 ​ — ​ — ​ — ​ 176 ​ — ​ Consumer ​ 604 ​ — ​ — ​ — ​ 604 ​ — ​ — Total Loans ​ $ 670,340 ​ $ 2,824 ​ $ 12,095 ​ $ 14,919 ​ $ 685,259 ​ $ 13,037 ​ $ — ​ The allowance for loan losses is established through a provision for loan losses charged to expense. The Company maintains the allowance at a level believed to cover all known and inherent losses in the portfolio that are both probable and reasonable to estimate at each reporting date. Management reviews the allowance for loan losses no less than quarterly in order to identify these inherent losses and to assess the overall collection probability for the loan portfolio in view of these inherent losses. For each primary type of loan, a loss factor is established reflecting an estimate of the known and inherent losses in such loan type contained in the portfolio using both a quantitative analysis as well as consideration of qualitative factors. The evaluation process includes, among other things, an analysis of delinquency trends, non-performing loan trends, the level of charge-offs and recoveries, prior loss experience, total loans outstanding, the volume of loan originations, the type, size and geographic concentration of the Company’s loans, the value of collateral securing the loans, the borrowers’ ability to repay and repayment performance, the number of loans requiring heightened management oversight, local economic conditions and industry experience. For the three months ended March 31, 2021 the analysis took into account the pandemic and its effects on the Company's business, especially with respect to commercial real estate, commercial business and construction and land development loans. Commercial real estate loans entail significant additional credit risks compared to owner-occupied one-to-four family residential mortgage loans, as they generally involve large loan balances concentrated with a single borrower or groups of related borrowers. In addition, the payment experience on loans secured by income-producing properties typically depends on the successful operation of the related real estate project and/or business operation of the borrower who is, in some cases, also the primary occupant, and thus may be subject to a greater extent to the effects of adverse conditions in the real estate market and in the economy in general. Commercial business loans typically involve a higher risk of default than residential loans of like duration since their repayment is generally dependent on the successful operation of the borrower’s business and the sufficiency of collateral, if any. Land acquisition, development and construction lending exposes the Company to greater credit risk than permanent mortgage financing. The repayment of land acquisition, development and construction loans depends upon the sale of the property to third parties and/or the availability of permanent financing upon completion of all improvements. These events may adversely affect the sale of the properties, potentially reducing both the borrowers’ ability to make required payments as well as reducing the value of the collateral property. Such lending is additionally subject to the risk that if the estimate of construction cost proves to be inaccurate, the Company potentially will be compelled to advance additional funds to allow completion of the project. In addition, if the estimate of value proves to be inaccurate, the Company may be confronted with a project, when completed, having less value than the loan amount. If the Company is forced to foreclose on a construction project prior to completion, there is no assurance that the Company would be able to recover the entire unpaid portion of the loan. The following tables summarize the primary segments of the allowance for loan losses. Activity in the allowance is presented for both the three and six month periods ended March 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ALLL balance at December 31, 2020 ​ $ 2,011 ​ $ 457 ​ $ 1,935 ​ $ 2,828 ​ $ 319 ​ $ — ​ $ 3 ​ $ 6 ​ $ 759 ​ $ 8,318 Charge-offs ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Recoveries ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 35 ​ ​ — ​ ​ 35 Provision ​ ​ (428) ​ ​ 263 ​ ​ 34 ​ ​ (118) ​ ​ 261 ​ ​ — ​ ​ — ​ ​ (36) ​ ​ 24 ​ ​ — ALLL balance at March 31, 2021 ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ 580 ​ $ — ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ALLL balance at September 30, 2020 ​ $ 1,877 ​ $ 460 ​ $ 1,989 ​ $ 2,888 ​ $ 194 ​ $ 89 ​ $ 3 ​ $ 6 ​ $ 797 ​ $ 8,303 Charge-offs ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Recoveries ​ ​ 1 ​ ​ — ​ ​ — ​ ​ — ​ ​ 14 ​ ​ — ​ ​ — ​ ​ 35 ​ ​ — ​ ​ 50 Provision ​ ​ (295) ​ ​ 260 ​ ​ (20) ​ ​ (178) ​ ​ 372 ​ ​ (89) ​ ​ — ​ ​ (36) ​ ​ (14) ​ ​ — ALLL balance at March 31, 2021 ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ 580 ​ $ — ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ​ ​ ​ ALLL balance at December 31, 2019 ​ $ 999 ​ $ 255 ​ $ 1,281 ​ $ 2,205 ​ $ 201 ​ $ 63 ​ $ 4 ​ $ 12 ​ $ 508 ​ $ 5,528 Charge-offs ​ ​ (3) ​ ​ - ​ ​ - ​ ​ - ​ ​ (15) ​ ​ — ​ ​ — ​ ​ (56) ​ ​ — ​ ​ (74) Recoveries ​ ​ 1 ​ ​ - ​ ​ - ​ ​ - ​ ​ - ​ ​ — ​ ​ — ​ ​ 6 ​ ​ — ​ ​ 7 Provision ​ ​ 304 ​ ​ 40 ​ ​ 84 ​ ​ -115 ​ ​ 71 ​ ​ 7 ​ ​ — ​ ​ 41 ​ ​ 68 ​ ​ 500 ALLL balance at March 31, 2020 ​ $ 1,301 ​ $ 295 ​ $ 1,365 ​ $ 2,090 ​ $ 257 ​ $ 70 ​ $ 4 ​ $ 3 ​ $ 576 ​ $ 5,961 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2020 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ​ ​ ​ ALLL balance at September 30, 2019 ​ $ 1,002 ​ $ 315 ​ $ 1,257 ​ $ 2,034 ​ $ 206 ​ $ 63 ​ $ 5 ​ $ 13 ​ $ 498 ​ $ 5,393 Charge-offs ​ ​ (3) ​ ​ — ​ ​ — ​ ​ — ​ ​ (15) ​ ​ — ​ ​ — ​ ​ (56) ​ ​ — ​ ​ (74) Recoveries ​ ​ 1 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 10 ​ ​ 6 ​ ​ — ​ ​ 17 Provision ​ ​ 301 ​ ​ (20) ​ ​ 108 ​ ​ 56 ​ ​ 66 ​ ​ 7 ​ ​ (11) ​ ​ 40 ​ ​ 78 ​ ​ 625 ALLL balance at March 31, 2020 ​ $ 1,301 ​ $ 295 ​ $ 1,365 ​ $ 2,090 ​ $ 257 ​ $ 70 ​ $ 4 ​ $ 3 ​ $ 576 ​ $ 5,961 ​ The Company recorded no provision for loan losses for the three and six month periods ended March 31, 2021, compared to a provision of $500,000 and $625,000 for loan losses for the three and six month periods in fiscal 2020. During the quarter ended March 31, 2021, the Company recorded no charge offs and recoveries of $35,000. During the six months ended March 31, 2021, the Company recorded no charge offs and recoveries of $50,000. During the quarter ended March 31, 2020, the Company recorded $74,000 in charge offs and recoveries of $7,000. During the six months ended March 31, 2020, the Company recorded charge offs of $74,000 and recoveries of $17,000. At March 31, 2021, the Company had four loans aggregating $4.9 million that were classified as TDRs. Three of the TDRs, totaling $4.5 million, which are on non-accrual, are a part of a troubled lending relationship totaling $10.1 million. The remaining TDR is also on non-accrual and consists of a $399,000 loan secured by a single-family property; the loan is performing in accordance with the restructured terms. The Company did not restructure any loans, as a TDR, during the three and six months ended March 31, 2021, or during the three and six months ending March 31, 2020. No TDRs defaulted during the three and six month periods ending March 31, 2021 or 2020.

DEPOSITS

DEPOSITS	6 Months Ended
	Mar. 31, 2021
DEPOSITS [Abstract]
DEPOSITS	6. DEPOSITS Deposits consist of the following major classifications: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ ​ 2021 ​ 2020 ​ ​ Amount Percent Amount Percent ​ ​ ​ (Dollars in Thousands) ​ Non-interest-bearing checking accounts ​ $ 32,253 4.1 % $ 30,002 3.9 % ​ Interest-bearing checking accounts ​ 112,752 14.2 % 135,797 17.6 % ​ Money market deposit accounts ​ 116,882 14.7 % 111,105 14.4 % ​ Passbook, club and statement savings ​ 229,936 29.0 % 224,435 29.1 % ​ Certificates maturing in six months or less ​ 162,045 20.4 % 125,165 16.2 % ​ Certificates maturing in more than six months ​ 139,877 17.6 % 144,445 18.8 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 793,745 100.0 % $ 770,949 100.0 % ​ ​ Certificates in the amount of $250,000 and over totaled $99.7 million as of March 31, 2021 and $76.6 million as of September 30, 2020.

ADVANCES FROM FEDERAL HOME LOAN

ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM	6 Months Ended
	Mar. 31, 2021
ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM
ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM	7. ADVANCES FROM FEDERAL HOME LOAN BANK – SHORT TERM As of March 31, 2021 and September 30, 2020 outstanding balances and related information regarding short-term borrowings from the FHLB are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, September 30, ​ (Dollar Amounts in Thousands) 2021 2020 ​ Balance at year-end ​ $ — ​ $ 25,000 ​ ​ Weight-average rate at period-end ​ — % 0.39 % ​ ​ As September 30, 2020, the $25.0 million of borrowings consisted of one 90-day FHLB advance associated with an interest rate swap contract. The Bank maintains borrowing facilities with the FHLB of Pittsburgh, Atlantic Community Bankers Bank (“ACBB”) and the Federal Reserve Bank of Philadelphia, the terms and interest rates of which are subject to change on the date of execution of borrowings. Available borrowings are based on collateral with the facility. The Bank also maintains unsecured borrowing facilities with ACBB and PNC for $12.5 million and $10.0 million, respectively. There were no draws on either facility as of March 31, 2021.

ADVANCES FROM FEDERAL HOME LO_2

ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM	6 Months Ended
	Mar. 31, 2021
ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM
ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM	8. ADVANCES FROM FEDERAL HOME LOAN BANK – LONG TERM Pursuant to collateral agreements with the FHLB of Pittsburgh, advances are secured by a blanket collateral of loans held by the Bank and qualifying fixed-income securities and FHLB stock. The long-term advances outstanding as of March 31, 2021 and September 30, 2020 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Lomg-term FHLB advances: ​ Maturity range ​ Weighted average ​ Stated interest rate range ​ March 31, ​ September 30, Description from to interest rate from to 2021 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in Thousands) Fixed Rate - Amortizing 1 ‑ Oct ‑ 20 30 ‑ Sep ‑ 21 ​ 2.80 % 2.72 % 2.83 % $ 1,074 ​ $ 5,179 Fixed Rate - Amortizing 1 ‑ Oct ‑ 21 30 ‑ Sep ‑ 22 ​ 2.88 % 1.99 % 3.05 % 3,886 ​ 5,523 Fixed Rate - Amortizing 1 ‑ Oct ‑ 22 30 ‑ Sep ‑ 23 ​ 2.89 % 1.94 % 3.11 % 4,414 ​ 5,265 Total ​ 2.87 % ​ ​ 9,374 ​ ​ 15,967 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Rate - Advances 1 ‑ Oct ‑ 20 30 ‑ Sep ‑ 21 ​ 2.30 % 1.42 % 2.35 % ​ 15,996 ​ ​ 17,996 Fixed Rate - Advances 1 ‑ Oct ‑ 21 30 ‑ Sep ‑ 22 ​ 2.31 % 1.94 % 3.23 % 63,272 ​ 63,293 Fixed Rate - Advances 1 ‑ Oct ‑ 22 30 ‑ Sep ‑ 23 ​ 2.52 % 2.00 % 3.22 % 94,999 ​ 94,999 Fixed Rate - Advances 1 ‑ Oct ‑ 23 30 ‑ Sep ‑ 24 ​ 2.88 % 2.38 % 3.20 % 67,998 ​ 67,998 Total ​ 2.55 % ​ ​ 242,265 ​ ​ 244,286 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2.57 % ​ Total ​ $ 251,639 ​ $ 260,253 ​

INTEREST RATE SWAPS

INTEREST RATE SWAPS	6 Months Ended
	Mar. 31, 2021
INTEREST RATE SWAPS
INTEREST RATE SWAPS	9. INTEREST RATE SWAPS The Bank has contracted with a third party to participate in interest rate swap contracts. There were thirteen cash flow hedges tied to wholesale funding at both March 31, 2021 and September 30, 2020. These interest rate swaps involve the receipt of variable-rate amounts from a counterparty in exchange for the Bank making fixed-rate payments. During the quarter ended March 31, 2021, $3,000 of income was recognized as ineffectiveness through earnings, while $4,000 of expense was recognized as ineffectiveness through earnings during the comparable period in fiscal 2020. During the six months ended March 31, 2020, $5,000 of expense was recognized as ineffectiveness through earnings, while $3,000 of expense was recognized as ineffectiveness through earnings during the comparable period in 2020. Below is a summary of the interest rate swap agreements and their terms as of March 31, 2021. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 Hedged ​ Notional ​ Pay Rate ​ Receive ​ Maturity Date ​ Unrealized Item Amount from to Rate from to ​ Loss (Dollars in Thousands) State and political subdivisions ​ $ 21,570 ​ 3.06 % 3.07 % 3 Mth Libor ​ 1-Feb-27 ​ 1-May-28 ​ $ (2,316) Commercial loans ​ 23,656 4.10 % 5.74 % 1 Mth Libor +225 to 276 bp ​ 13-Jun-25 ​ 1-Aug-26 ​ — 30 day wholesale funding ​ ​ 90,000 ​ 1.36 % 2.70 % 1 Mth Libor ​ 15-Feb-24 ​ 12-Jun-26 ​ ​ (4,099) 90 day wholesale funding ​ ​ 135,000 ​ 2.51 % 2.78 % 3 Mth Libor ​ 11-Jan-24 ​ 27-Mar-24 ​ ​ (8,466) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (14,881) ​ Below is a summary of the interest rate swap agreements and their terms as of September 30, 2020. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 Hedged ​ Notional ​ Pay Rate ​ Receive ​ Maturity Date ​ Unrealized Item Amount from to Rate from to Loss (Dollars in T housands) State and political subdivisions ​ $ 21,570 ​ 3.06 % 3.07 % 3 Mth Libor ​ 1-Feb-27 ​ 1-May-28 ​ $ (3,834) Commercial loans ​ 23,656 4.10 % 5.74 % 1 Mth Libor +225 to 276 bp ​ 13-Jun-25 ​ 1-Aug-26 ​ — 30 day wholesale funding ​ ​ 90,000 ​ 1.36 % 2.70 % 1 Mth Libor ​ 15-Feb-24 ​ 12-Jun-26 ​ ​ (6,157) 90 day wholesale funding ​ ​ 135,000 ​ 2.51 % 2.78 % 3 Mth Libor ​ 11-Jan-24 ​ 27-Mar-24 ​ ​ (10,969) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (20,960) ​ All interest swaps are carried at fair value in accordance with FASB ASC 815 “Derivatives and Hedging.”

INCOME TAXES

INCOME TAXES	6 Months Ended
	Mar. 31, 2021
INCOME TAXES
INCOME TAXES	10. INCOME TAXES Items that gave rise to significant portions of deferred income taxes are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ 2021 2020 ​ ​ ​ (Dollars in Thousands) ​ Deferred tax assets: ​ ​ ​ Allowance for loan losses ​ $ 2,074 ​ $ 2,071 ​ Nonaccrual interest ​ 625 ​ 561 ​ Accrued vacation ​ 16 ​ 16 ​ Capital loss carryforward ​ 4 ​ 4 ​ Split dollar life insurance ​ 9 ​ 9 ​ Post-retirement benefits ​ 70 ​ 72 ​ Realized loss on equity securities ​ — ​ 3 ​ Unrealized losses on interest rate swaps ​ ​ 2,637 ​ ​ 3,596 ​ Deferred compensation ​ 756 ​ 781 ​ Goodwill ​ 52 ​ 58 ​ Lease liability ​ ​ 276 ​ ​ — ​ Other ​ 104 ​ 48 ​ Employee benefit plans ​ 214 ​ 187 ​ Total deferred tax assets ​ 6,837 ​ 7,406 ​ Valuation allowance ​ (4) ​ (4) ​ Total deferred tax assets, net of valuation allowance ​ 6,833 ​ 7,402 ​ ​ ​ ​ ​ Deferred tax liabilities: ​ ​ ​ Property ​ 173 ​ 137 ​ Right of Use ​ ​ 251 ​ ​ — ​ Realized gain on equity securities ​ ​ 9 ​ ​ — ​ Unrealized gains on available for sale securities ​ ​ 2,227 ​ ​ 2,813 ​ Purchase accounting adjustments ​ 359 ​ 321 ​ Deferred loan fees ​ 401 ​ 229 ​ Total deferred tax liabilities ​ 3,420 ​ 3,500 ​ Net deferred tax assets ​ $ 3,413 ​ $ 3,902 ​ ​ The Company establishes a valuation allowance for deferred tax assets when management believes that the use of the deferred tax assets is not likely to be fully realized through future reversals of existing taxable temporary differences and/or, to a lesser extent, future taxable income. The tax deduction generated by the redemption of the shares of a mutual fund held by the Bank and the subsequent impairment charge on the assets acquired through the redemption in kind are considered capital losses and can only be utilized to the extent of capital gains recognized over a five year period, resulting in the establishment of a valuation allowance for the carryforward period. The valuation allowance totaled $4,000 at both March 31, 2021 and September 30, 2020. There is currently no liability for uncertain tax positions and no known unrecognized tax benefits. The Company recognizes, when applicable, interest and penalties related to unrecognized tax benefits in the provision for income taxes in the consolidated statements of operations as a component of income tax expense. The Company’s federal and state income tax returns for taxable years through September 30, 2016 have been closed for purposes of examination by the Internal Revenue Service and the Pennsylvania Department of Revenue.

STOCK COMPENSATION PLANS

STOCK COMPENSATION PLANS	6 Months Ended
	Mar. 31, 2021
STOCK COMPENSATION PLANS
STOCK COMPENSATION PLANS	11. STOCK COMPENSATION PLANS The Company maintains the 2008 Recognition and Retention Plan (“RRP”) which is administered by a committee of the Board of Directors of the Company. The RRP provides for the grant of shares of common stock of the Company to officers, employees and directors of the Company. In order to fund the grant of shares under the RRP, the RRP purchased 213,528 shares (on a converted basis) of the Company’s common stock in the open market for an aggregating cost of approximately $2.5 million, at an average purchase price per share of $11.49. The Company made sufficient contributions to the RRP to fund these purchases. During February 2015, shareholders approved the 2014 Stock Incentive Plan (the “2014 SIP”). As part of the 2014 SIP, a maximum of 285,655 shares of common stock can be awarded as restricted stock awards or units, of which 233,500 shares were awarded during February 2015. In August 2016, the Company granted 7,473 awards covering shares under the RRP and 3,027 shares under the 2014 SIP. In March 2017, the Company granted awards covering 17,128 shares under the 2014 SIP. In March 2018, the Company granted awards covering 8,209 shares under the RRP and 18,291 shares under the 2014 SIP. Shares subject to awards under either plan generally vest at the rate of 20% per year over five years. No further grants may be made pursuant to the RRP in accordance with its terms. Compensation expense related to the shares subject to restricted stock awards granted is recognized ratably over the five-year vesting period in an amount which totals the grant date fair value multiplied by the number of shares subject to the grant. During the three and six months ended March 31, 2021, an aggregate of $41,000 and $84,000, respectively, was recognized in compensation expense for the grants pursuant to the RRP and the 2014 SIP. During the three and six months ended March 31, 2020, $120,000 and $256,000, respectively, was recognized in compensation expense for the grants pursuant to the RRP and the 2014 SIP. At March 31, 2021, approximately $239,000 in additional compensation expense for unvested shares awarded related to the RRP and 2014 SIP remained unrecognized. A summary of the Company’s non-vested stock award activity for the six months ended March 31, 2021 is presented in the following table: ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ March 31, 2021 ​ ​ Number of ​ Weighted Average ​ Shares Grant Date Fair Value Non-vested stock awards at October 1, 2020 23,056 ​ $ 17.78 Granted — ​ — Forfeited — ​ — Vested (8,128) ​ 18.03 Non-vested stock awards at March 31, 2021 14,928 ​ $ 17.66 ​ The Company maintains the 2008 Stock Option Plan (the “Option Plan”) which authorizes the grant of stock options to officers, employees and directors of the Company to acquire shares of common stock with an exercise price at least equal to the fair market value of the common stock on the grant date. Options generally become vested and exercisable at the rate of 20% per year over five years and are generally exercisable for a period of ten years after the grant date. A total of 533,808 shares (on a converted basis) of common stock were approved for future issuance pursuant to the Option Plan. As of September 30, 2018, all of the options had been awarded under the Option Plan. The 2014 SIP reserved up to 714,145 shares for issuance pursuant to options. Options to purchase 605,000 shares were awarded during February 2015 pursuant to the 2014 SIP. During August 2016, the Company granted options covering 18,866 shares under the Option Plan and 8,634 shares under the 2014 SIP. In March 2017, the Company granted options covering 22,828 shares under the 2014 SIP. In May 2017, the Company granted options covering 25,000 shares under the 2014 SIP and 283 shares under the Option Plan. In March 2018, the Company granted options covering 159,265 shares under the 2014 SIP and 18,235 shares under the Option Plan. In July 2019, the Company granted options covering 39,702 shares under the 2014 SIP. In September 2020, the Company granted 12,500 shares under the 2014 SIP. No further grants may be made pursuant to the Option Plan. A summary of the status of the Company’s stock options under the Option Plan and the 2014 SIP as of March 31, 2021 is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ March 31, 2021 ​ Number of Weighted Average ​ ​ Shares ​ Exercise Price Options outstanding at October 1, 2020 571,258 ​ $ 14.58 Granted — ​ — Exercised (15,000) ​ 12.23 Forfeited (39,500) ​ 18.42 Outstanding at March 31, 2021 516,758 ​ $ 14.36 Exercisable at March 31, 2021 400,231 ​ $ 13.70 ​ The weighted average remaining contractual term was approximately 5.1 years for options outstanding as of March 31, 2021. The estimated fair value of options granted during fiscal 2009 was $2.98 per share, $2.92 for options granted during fiscal 2010, $3.34 for options granted during fiscal 2013, $4.67 for the options granted during fiscal 2014, $4.58 for options granted during fiscal 2015, $2.13 for options granted during fiscal 2016, $3.18 for options granted during fiscal 2017, $3.63 for options granted during fiscal 2018, $3.38 for options granted in fiscal 2019 and $2.31 for options granted in 2020. The fair value for grants made in fiscal 2017 was estimated on the date of grant using the Black-Scholes pricing model with the following assumptions: an exercise and fair value of $17.43, term of seven years, volatility rate of 14.37%, interest rate of 2.22% and a yield rate of 0.69%. The fair value for grants made in fiscal 2018 was estimated on the date of grant using the Black-Scholes pricing model with the following assumptions: an exercise and fair value of $18.46, term of seven years, volatility rate of 15.90%, interest rate of 2.82% and a yield rate of 1.08%. The fair value for grants made in fiscal 2019 was estimated on the date of grant using the Black-Scholes pricing model with the following assumptions: an exercise and fair value of $18.16, term of seven years, volatility rate of 17.76%, interest rate of 1.87% and a yield rate of 1.10%. The fair value for grants made in fiscal 2020 was estimated on the date of grant using the Black-Scholes pricing model with the following assumptions: an exercise and fair value of $10.00, term of seven years, volatility rate of 33.22%, interest rate of 0.41% and a yield rate of 2.80%. During the three and six months ended March 31, 2021, $41,000 and $84,000, respectively, was recognized in compensation expense for options granted pursuant to the Option Plan and the 2014 SIP. During the three and six months ended March 31, 2020, $117,000 and $270,000, respectively, was recognized in compensation expense for options granted pursuant to the Option Plan and the 2014 SIP. At March 31, 2021, there was approximately $339,000 in additional compensation expense to be recognized for awarded options which remained outstanding and unvested at such date. The weighted average period over which this expense will be recognized is approximately 2.4 years.

COMMITMENTS AND CONTINGENT LIAB

COMMITMENTS AND CONTINGENT LIABILITIES	6 Months Ended
	Mar. 31, 2021
COMMITMENTS AND CONTINGENT LIABILITIES
COMMITMENTS AND CONTINGENT LIABILITIES	12. COMMITMENTS AND CONTINGENT LIABILITIES At March 31, 2021, the Company had $55.0 million in outstanding commitments to originate loans with market interest rates ranging from 3.13% to 4.50%. At September 30, 2020, the Company had $29.9 million in outstanding commitments to originate loans with market interest rates ranging from 3.25% to 4.75%. The aggregate undisbursed portion of loans-in-process amounted to $89.9 million at March 31, 2021 and $86.9 million at September 30, 2020. The Company also had commitments under unused lines of credit of $45.9 million as of March 31, 2021 and $40.1 million as of September 30, 2020 and letters of credit outstanding of $1.1 million as of March 31, 2021 and $1.1 million as of September 30, 2020. Among the Company’s contingent liabilities are exposures to limited recourse arrangements with respect to the Company’s sales of whole loans and participation interests. At March 31, 2021, the exposure, which represents a portion of credit risk associated with the interests sold, amounted to $1.0 million. This exposure is for the life of the related loans and payables, on our proportionate share, as actual losses are incurred. The Company is involved in various legal proceedings occurring in the ordinary course of business. Management of the Company, based on discussions with litigation counsel, believes that such proceedings will not have a material adverse effect on the financial condition, operations or cash flows of the Company. However, there can be no assurance that any of the outstanding legal proceedings to which the Company is a party will not be decided adversely to the Company’s interests and not have a material adverse effect on the financial condition and operations of the Company.

FAIR VALUE MEASUREMENT

FAIR VALUE MEASUREMENT	6 Months Ended
	Mar. 31, 2021
FAIR VALUE MEASUREMENT
FAIR VALUE MEASUREMENT	13. FAIR VALUE MEASUREMENT The fair value estimates presented herein are based on pertinent information available to management as of March 31, 2021 and September 30, 2020, respectively. Although management is not aware of any factors that would significantly affect the fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since that date and, therefore, current estimates of fair value may differ significantly from the amounts presented herein. Generally accepted accounting principles used in the United States establish a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value. The three broad levels of hierarchy are as follows: Level 1 Quoted prices in active markets for identical assets or liabilities. Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities; Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. Those assets and liabilities as of March 31, 2021 which are measured at fair value on a recurring basis are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Category Used for Fair Value Measurement ​ Level 1 Level 2 Level 3 Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ ​ Securities available for sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government and agency obligations ​ $ — ​ $ 10,893 ​ $ — ​ $ 10,893 State and political subdivisions ​ — ​ 79,351 ​ — ​ 79,351 Mortgage-backed securities - U.S. Government agencies ​ — ​ 179,701 ​ — ​ 179,701 Corporate bonds ​ — ​ 83,862 ​ — ​ 83,862 Equity securities ​ 54 ​ — ​ — ​ 54 Total ​ $ 54 ​ $ 353,807 ​ $ — ​ $ 353,861 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap contracts ​ $ — ​ $ 14,881 ​ $ — ​ $ 14,881 Total ​ $ — ​ $ 14,881 ​ $ — ​ $ 14,881 ​ Those assets and liabilities as of September 30, 2020 which are measured at fair value on a recurring basis are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Category Used for Fair Value Measurement ​ Level 1 Level 2 Level 3 Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ ​ Securities available for sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government and agency obligations ​ $ — ​ $ 22,394 ​ $ — ​ $ 22,394 State and political subdivisions ​ ​ — ​ 79,621 ​ — ​ 79,621 Mortgage-backed securities - U.S. Government agencies ​ — ​ 236,566 ​ — ​ 236,566 Corporate bonds ​ — ​ 81,783 ​ — ​ 81,783 Equity securities ​ 51 ​ — ​ — ​ 51 Total ​ $ 51 ​ $ 420,364 ​ $ — ​ $ 420,415 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap contracts ​ $ — ​ $ 20,960 ​ $ — ​ $ 20,960 Total ​ $ — ​ $ 20,960 ​ $ — ​ $ 20,960 ​ The fair value of financial instruments has been determined by the Company using available market information and appropriate valuation methodologies. However, considerable judgment is necessarily required to interpret market data to develop the estimates of fair value. Accordingly, the estimates presented herein are not necessarily indicative of the amounts the Company could realize in a current market exchange. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements at ​ ​ Carrying ​ Fair ​ March 31, 2021 ​ Amount Value (Level 1) (Level 2) (Level 3) ​ ​ (Dollars in Thousands) ​ ​ ​ Assets: ​ ​ ​ ​ ​ Investment and mortgage-backed securities held to maturity ​ $ 22,270 ​ $ 23,460 ​ $ — ​ $ 23,460 ​ $ — Loans receivable, net ​ ​ 620,875 ​ ​ 622,637 ​ ​ — ​ ​ — ​ ​ 622,637 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Certificates of deposit ​ ​ 301,922 ​ ​ 311,058 ​ ​ 311,058 ​ ​ — ​ ​ — Advances from FHLB - long-term ​ ​ 251,639 ​ ​ 261,171 ​ ​ 261,171 ​ ​ — ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements at ​ ​ Carrying ​ Fair ​ September 30, 2020 ​ Amount Value (Level 1) (Level 2) (Level 3) ​ ​ (Dollars in Thousands) ​ ​ ​ Assets: ​ ​ ​ ​ ​ Investment and mortgage-backed securities held to maturity ​ $ 22,860 ​ $ 24,330 ​ $ — ​ $ 24,330 ​ $ — Loans receivable, net ​ ​ 588,300 ​ ​ 593,768 ​ ​ ​ ​ ​ ​ ​ ​ 593,768 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Certificates of deposit ​ ​ 269,610 ​ ​ 278,224 ​ ​ 278,224 ​ ​ — ​ ​ — Advances from FHLB - long-term ​ ​ 260,253 ​ ​ 274,172 ​ ​ 274,172 ​ ​ — ​ ​ — ​

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	6 Months Ended
	Mar. 31, 2021
GOODWILL AND OTHER INTANGIBLE ASSETS
GOODWILL AND OTHER INTANGIBLE ASSETS	14. GOODWILL AND OTHER INTANGIBLE ASSETS The Company’s goodwill and intangible assets are related to the acquisition of Polonia Bancorp, Inc. on January 1, 2017. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ October 1, ​ Additions/ ​ ​ ​ ​ March 31, ​ Amortization ​ 2020 Adjustments Amortization 2021 Period ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in Thousands) ​ ​ Goodwill ​ $ 6,102 ​ $ — ​ $ — ​ $ 6,102 Core deposit intangible ​ 340 ​ — ​ (49) ​ 291 10 years ​ ​ $ 6,442 ​ $ — ​ $ (49) ​ $ 6,393 ​ As of March 31, 2021, the current fiscal year and the future fiscal periods amortization expense for the core deposit intangible is: ​ ​ ​ ​ ​ (in Thousands) ​ ​ ​ ​ ​ ​ 2021 ​ $ 44 2022 ​ 78 2023 ​ 64 2024 ​ 49 2025 ​ 34 Thereafter ​ 22 ​ ​ $ 291 ​

LEASES

LEASES	6 Months Ended
	Mar. 31, 2021
LEASES [Abstract]
LEASES	15. LEASES Operating leases in which the Company is the lessee are recorded as operating lease Right of Use ("ROU") assets and operating lease liabilities, included in other assets and other liabilities, respectively, on the consolidated statement of financial condition. The Company does not currently have any finance leases. Operating lease ROU assets represent the right to use an underlying asset during the lease term and operating lease liabilities represent the obligation to make lease payments arising from the lease. ROU assets and operating lease liabilities were recognized on October 1, 2019, the date of adoption of ASU 2016-02 based on the present value of the remaining lease payments using a discount rate that represents the Company's incremental borrowing rate at the date of initial application. Operating lease expense, which is comprised of amortization of the ROU assets and the implicit interest accreted on the operating lease liability, is recognized on a straight line basis over the lease term of the operating lease, and is recorded in office occupancy expense in the consolidated statements of operations. The leases relate to Bank branches with remaining lease terms of generally five As of March 31, 2021, operating lease ROU assets were $1.2 million and operating lease liabilities were $1.3 million. Operating lease costs of $51,000 and $102,000, respectively, were recognized for the three and six month periods ended March 31, 2021. The following table summarizes other information related to our operating leases: ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Weighted-average remaining lease term - operating leases in years 6.85 ​ Weighted-average discount rate - operating leases 2.0 % ​ The following table presents aggregate lease maturities and obligations as of March 31, 2021: ​ ​ ​ ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ 2021 ​ $ 105 2022 ​ 213 2023 ​ 216 2024 ​ 220 2025 ​ 231 2025 and thereafter ​ ​ 423 Total lease payments ​ ​ 1,408 Less: interest ​ 96 Present value of lease liabilities ​ $ 1,312 ​

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
	Mar. 31, 2021
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Basis of presentation	Basis of presentation –
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements —
Recently Adopted Accounting Pronouncements	Recent Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments Update for SEC filers that are eligible to be smaller reporting companies, non-SEC filers, and all other companies to fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We expect to recognize a one-time cumulative effect adjustment to the allowance for loan losses as of the beginning of the first reporting period in which the new standard is effective, but cannot yet determine the magnitude of any such one-time adjustment or the overall impact of the new guidance on the consolidated financial statements. In May 2019, the FASB issued ASU 2019-05, Financial Instruments – Credit Losses, Topic 326, which allows entities to irrevocably elect the fair value option for certain financial assets previously measured at amortized cost upon adoption of the new credit losses standard. To be eligible for the transition election, the existing financial asset must otherwise be both within the scope of the new credit losses standard and eligible for the applying the fair value option in ASC 825-10-3. The election must be applied on an instrument-by-instrument basis and is not available for either available-for-sale or held-to-maturity debt securities. For entities that elect the fair value option, the difference between the carrying amount and the fair value of the financial asset would be recognized through a cumulative-effect adjustment to opening retained earnings as of the date an entity adopted ASU 2016-13. Changes in fair value of that financial asset would subsequently be reported in current earnings. For entities that have not yet adopted ASU 2016-13, the effective dates and transition requirements are the same as those in ASU 2016-13. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and or results of operations. In November 2019, the FASB issued ASU 2019-10, Financial Instruments ‒ Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842) In January 2020, the FASB issued ASU 2020-4, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, March 2020, to provide temporary optional expedients and exceptions to the U.S. GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens of the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates, such as Secured Overnight Financing Rate. Entities can elect not to apply certain modification accounting requirements to contracts affected by what the guidance calls reference rate reform, if certain criteria are met. An entity that makes this election would not have to remeasure the contracts at the modification date or reassess a previous accounting determination. Also, entities can elect various optional expedients that would allow them to continue applying hedge accounting for hedging relationships affected by reference rate reform, if certain criteria are met, and can make a one-time election to sell and/or reclassify held-to-maturity debt securities that reference an interest rate affected by reference rate reform. The amendments in this ASU are effective for all entities upon issuance through March 31, 2022. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and/or results of operations. ​ In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848) certain hedging relationships existing as of December 31, 2022, that apply certain optional expedients in which the accounting effects are recorded through the end of the hedging relationship. The Company is currently evaluating the impact the adoption of the standard will have on the Company’s financial position and/or results of operations.

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	6 Months Ended
	Mar. 31, 2021
EARNINGS PER SHARE
Schedule of basic and diluted earnings per share	The calculated basic and diluted earnings per share are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ ​ 2021 ​ 2020 ​ ​ ​ (Dollars in Thousands Except Per Share Data) ​ ​ Basic Diluted Basic Diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 1,715 ​ $ 1,715 ​ $ 2,924 ​ $ 2,924 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding ​ 7,975,683 ​ 7,975,683 ​ 8,884,760 ​ 8,884,760 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of CSEs ​ — ​ 14,671 ​ — ​ 117,342 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Adjusted weighted average common shares used in earnings per share computation ​ 7,975,683 ​ 7,990,354 ​ 8,884,760 ​ 9,002,102 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per share ​ $ 0.22 ​ $ 0.21 ​ $ 0.33 ​ $ 0.32 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, ​ ​ 2021 ​ 2020 ​ ​ (Dollars in Thousands, Except Share and Per Share Data) ​ Basic Diluted Basic Diluted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 3,551 ​ $ 3,551 ​ $ 5,387 ​ $ 5,387 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average common shares outstanding ​ 8,040,907 ​ 8,040,907 ​ 8,885,972 ​ 8,885,972 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Effect of CSEs ​ — ​ 4,512 ​ — ​ 133,815 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Adjusted weighted average common shares used in earnings per share computation ​ 8,040,907 ​ 8,045,419 ​ 8,885,972 ​ 9,019,787 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings per share ​ $ 0.44 ​ $ 0.44 ​ $ 0.61 ​ $ 0.60

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	6 Months Ended
	Mar. 31, 2021
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) [Abstract]
Schedule of changes in accumulated other comprehensive (loss) income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ Three Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ ​ ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ ​ securities (a) (a) income (loss) securities (a) (a) income (loss) ​ Beginning balance, January 1 ​ $ 12,221 ​ $ (12,428) ​ $ (207) ​ $ 6,920 ​ $ (5,096) ​ $ 1,824 ​ Other comprehensive (loss) income before reclassification ​ (3,842) ​ 2,500 ​ (1,342) ​ 3,812 ​ (8,621) ​ (4,809) ​ Total other comprehensive income (loss) ​ 8,379 ​ (9,928) ​ (1,549) ​ 10,732 ​ (13,717) ​ (2,985) ​ Reclassification for net gains recorded in net income ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,868) ​ ​ — ​ ​ (1,868) ​ Ending balance, March 31 ​ $ 8,379 ​ $ (9,928) ​ $ (1,549) ​ $ 8,864 ​ $ (13,717) ​ $ (4,853) ​ (a) All amounts are net of tax. Amounts in parentheses indicate debits. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ Six Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ Total ​ ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ ​ ​ ​ ​ ​ accumulated ​ ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ Unrealized gain ​ Unrealized gain (loss) ​ other ​ ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ (loss) on AFS ​ on interest rate swaps ​ comprehensive ​ securities (a) (a) income (loss) securities (a) (a) income (loss) Beginning balance, October 1 ​ $ 10,585 ​ $ (13,528) ​ $ (2,943) ​ $ 8,098 ​ $ (6,906) ​ $ 1,192 Other comprehensive (loss) income before reclassification ​ (2,206) ​ 3,600 ​ 1,394 ​ 2,885 ​ (6,811) ​ (3,926) Total other comprehensive income (loss) ​ 8,379 ​ (9,928) ​ (1,549) ​ 10,983 ​ (13,717) ​ (2,734) Reclassification for net gains recorded in net income ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,119) ​ ​ — ​ ​ (2,119) Ending balance, March 31 ​ $ 8,379 ​ $ (9,928) ​ $ (1,549) ​ $ 8,864 ​ $ (13,717) ​ $ (4,853) ​ (a) All amounts are net of tax. Amounts in parentheses indicate debits.

INVESTMENT AND MORTGAGE-BACKE_2

INVESTMENT AND MORTGAGE-BACKED SECURITIES (Tables)	6 Months Ended
	Mar. 31, 2021
INVESTMENT AND MORTGAGE-BACKED SECURITIES
Schedule of amortized cost and fair value of securities, with gross unrealized gains and losses	The amortized cost and fair value of investment and mortgage-backed securities, with gross unrealized gains and losses, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency obligations ​ $ 10,811 ​ $ 82 ​ $ — ​ $ 10,893 State and political subdivisions ​ 77,437 ​ 2,560 ​ (646) ​ 79,351 Mortgage-backed securities - U.S. government agencies ​ ​ 174,243 ​ ​ 6,387 ​ ​ (929) ​ ​ 179,701 Corporate debt securities ​ 80,709 ​ 3,337 ​ (184) ​ 83,862 Total debt securities available for sale ​ $ 343,200 ​ $ 12,366 ​ $ (1,759) ​ $ 353,807 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held to Maturity: ​ ​ ​ ​ U.S. government and agency obligations ​ $ 1,000 ​ $ 185 ​ $ — ​ $ 1,185 State and political subdivisions ​ 18,022 ​ 738 ​ — ​ 18,760 Mortgage-backed securities - U.S. government agencies ​ 3,248 ​ 267 ​ — ​ 3,515 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities held to maturity ​ $ 22,270 ​ $ 1,190 ​ $ — ​ $ 23,460 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Fair ​ Cost Gains Losses Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency obligations ​ $ 22,241 ​ $ 153 ​ $ — ​ $ 22,394 State and political subdivisions ​ ​ 79,099 ​ 1,940 ​ (1,418) ​ 79,621 Mortgage-backed securities - U.S. government agencies ​ 226,863 ​ ​ 9,774 ​ ​ (71) ​ ​ 236,566 Corporate debt securities ​ 78,764 ​ 3,564 ​ (545) ​ 81,783 Total debt securities ​ $ 406,967 ​ $ 15,431 ​ $ (2,034) ​ $ 420,364 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities Held to Maturity: ​ ​ ​ ​ U.S. government and agency obligations ​ $ 1,000 ​ $ 236 ​ $ — ​ $ 1,236 State and political subdivisions ​ 18,076 ​ 925 ​ — ​ 19,001 Mortgage-backed securities - U.S. government agencies ​ 3,784 ​ 309 ​ — ​ 4,093 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities held to maturity ​ $ 22,860 ​ $ 1,470 ​ $ — ​ $ 24,330 ​
Schedule of gross unrealized losses and related fair values of investment securities	The following table shows the gross unrealized losses and related fair values of the Company’s investment and mortgage-backed securities, aggregated by investment category and length of time that individual securities had been in a continuous loss position as of March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less than 12 months ​ More than 12 months ​ Total ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ Fair ​ Unrealized ​ Fair ​ Unrealized ​ Fair ​ Losses Value Losses Value Losses Value ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State and political subdivisions ​ $ (136) ​ $ 10,686 ​ $ (510) ​ $ 6,838 ​ $ (646) ​ $ 17,524 Mortgage-backed securities -U.S. government agencies ​ (929) ​ 25,777 ​ — ​ — ​ (929) ​ 25,777 Corporate debt securities ​ (184) ​ 11,816 ​ — ​ — ​ (184) ​ 11,816 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities available for sale ​ $ (1,249) ​ $ 48,279 ​ $ (510) ​ $ 6,838 ​ $ (1,759) ​ $ 55,117 ​ The following table shows the gross unrealized losses and related fair values of the Company’s investment and mortgage-backed securities, aggregated by investment category and length of time that individual securities had been in a continuous loss position as of September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less than 12 months ​ More than 12 months ​ Total ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Unrealized Fair Unrealized Fair Unrealized Fair ​ ​ Losses ​ Value ​ Losses ​ Value ​ Losses ​ Value ​ ​ (Dollars in Thousands) Securities Available for Sale: ​ ​ ​ ​ ​ ​ ​ ​ State and political subdivisions ​ $ (126) ​ $ 10,735 ​ $ (1,292) ​ $ 24,510 ​ $ (1,418) ​ $ 35,245 Mortgage-backed securities - US government agencies ​ (66) ​ 10,025 ​ (5) ​ 584 ​ (71) ​ 10,609 Corporate debt securities ​ (545) ​ 16,472 ​ — ​ — ​ (545) ​ 16,472 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total securities available for sale ​ $ (737) ​ $ 37,232 ​ $ (1,297) ​ $ 25,094 ​ $ (2,034) ​ $ 62,326 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of amortized cost and fair value of debt securities by contractual maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Held to Maturity ​ Available for Sale ​ Amortized Fair Amortized Fair ​ ​ Cost ​ Value ​ Cost ​ Value ​ ​ (Dollars in Thousands) Due after one through five years ​ $ 5,693 ​ $ 6,085 ​ $ 31,190 ​ $ 32,832 Due after five through ten years ​ 9,284 ​ 9,594 ​ 50,705 ​ 52,297 Due after ten years ​ 4,045 ​ 4,266 ​ 87,062 ​ 88,977 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 19,022 ​ $ 19,945 ​ $ 168,957 ​ $ 174,106

LOANS RECEIVABLE (Tables)

LOANS RECEIVABLE (Tables)	6 Months Ended
	Mar. 31, 2021
LOANS RECEIVABLE
Schedule of loans receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ 2021 2020 ​ ​ ​ (Dollars in Thousands) ​ One-to-four family residential ​ $ 210,569 ​ $ 233,872 ​ Multi-family residential ​ 52,657 ​ 31,100 ​ Commercial real estate ​ 149,385 ​ 139,943 ​ Construction and land development ​ 264,618 ​ 260,648 ​ Loans to financial institutions ​ — ​ 6,000 ​ Commercial business ​ 41,882 ​ 12,916 ​ Leases ​ 117 ​ 176 ​ Consumer ​ 515 ​ 604 ​ ​ ​ ​ ​ ​ ​ ​ ​ Total loans ​ 719,743 ​ 685,259 ​ ​ ​ ​ ​ ​ ​ ​ ​ Undisbursed portion of loans-in-process ​ (89,912) ​ (86,862) ​ Deferred loan fees ​ (603) ​ (1,794) ​ Allowance for loan losses ​ (8,353) ​ (8,303) ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loans ​ $ 620,875 ​ $ 588,300 ​
Schedule of loans individually and collectively evaluated for impairment by loan segment	The following table summarizes by loan segment the balance in the allowance for loan losses and the loans individually and collectively evaluated for impairment by loan segment at March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to ​ ​ ​ ​ ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four- ​ Multi-family ​ Commercial ​ Construction and ​ financial ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ family residential ​ residential ​ real estate ​ land development ​ institutions ​ business ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ ​ ​ $ — Collectively evaluated for impairment ​ ​ 1,583 ​ ​ 720 ​ ​ 1,969 ​ ​ 2,710 ​ ​ — ​ ​ 580 ​ ​ 3 ​ ​ 5 ​ ​ 783 ​ ​ 8,353 Total ending allowance balance ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ — ​ $ 580 ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,475 ​ $ — ​ $ 1,328 ​ $ 8,250 ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ $ 13,053 Collectively evaluated for impairment ​ 207,094 ​ 52,657 ​ 148,057 ​ 256,368 ​ — ​ 41,882 ​ 117 ​ 515 ​ ​ ​ ​ 706,690 Total loans ​ $ 210,569 ​ $ 52,657 ​ $ 149,385 ​ $ 264,618 ​ $ — ​ $ 41,882 ​ $ 117 ​ $ 515 ​ ​ ​ ​ $ 719,743 ​ The following table summarizes by loan segment the balance in the allowance for loan losses and the loans individually and collectively evaluated for impairment by loan segment at September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four- ​ Multi-family ​ Commercial ​ Construction and ​ financial ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ family residential residential real estate land development institutions ​ business Leases Consumer ​ Unallocated Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ ​ ​ $ — Collectively evaluated for impairment ​ ​ 1,877 ​ ​ 460 ​ ​ 1,989 ​ ​ 2,888 ​ ​ 89 ​ ​ 194 ​ ​ 3 ​ ​ 6 ​ ​ 797 ​ ​ 8,303 Total ending allowance balance ​ $ 1,877 ​ $ 460 ​ $ 1,989 ​ $ 2,888 ​ $ 89 ​ $ 194 ​ $ 3 ​ $ 6 ​ $ 797 ​ $ 8,303 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,095 ​ $ — ​ $ 1,417 ​ $ 8,525 ​ $ — ​ $ — ​ $ — ​ $ — ​ ​ ​ ​ $ 13,037 Collectively evaluated for impairment ​ 230,777 ​ 31,100 ​ 138,526 ​ 252,123 ​ 6,000 ​ 12,916 ​ 176 ​ 604 ​ ​ ​ ​ 672,222 Total loans ​ $ 233,872 ​ $ 31,100 ​ $ 139,943 ​ $ 260,648 ​ $ 6,000 ​ $ 12,916 ​ $ 176 ​ $ 604 ​ ​ ​ ​ $ 685,259
Schedule of impaired loans by class, segregated by those for which a specific allowance was required and those for which a specific allowance was not necessary	The following table presents impaired loans by class as of March 31, 2021, segregated by those for which a specific allowance was required and those for which no specific allowance was required. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans with ​ ​ ​ ​ ​ ​ ​ ​ Impaired Loans with ​ No Specific ​ ​ ​ ​ ​ ​ Specific Allowance ​ Allowance ​ Total Impaired Loans ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid ​ ​ Recorded ​ Related ​ Recorded ​ Recorded ​ Principal ​ Investment Allowance Investment Investment Balance One-to-four family residential ​ $ — ​ $ — ​ $ 3,475 ​ $ 3,475 ​ $ 3,792 Commercial real estate ​ — ​ — ​ 1,328 ​ 1,328 ​ 1,505 Construction and land development ​ — ​ — ​ 8,250 ​ 8,250 ​ 10,631 Total ​ $ — ​ $ — ​ $ 13,053 ​ $ 13,053 ​ $ 15,928 ​ The following table presents impaired loans by class as of September 30, 2020, segregated by those for which a specific allowance was required and those for which no specific allowance was required. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Impaired ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans with ​ ​ ​ ​ ​ ​ Impaired Loans with ​ No Specific ​ ​ ​ ​ ​ ​ ​ ​ Specific Allowance Allowance Total Impaired Loans ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid ​ ​ Recorded Related Recorded Recorded Principal ​ Investment Allowance Investment Investment Balance One-to-four family residential ​ $ — ​ $ — ​ $ 3,095 ​ $ 3,095 ​ $ 3,482 Commercial real estate ​ — ​ — ​ 1,417 ​ 1,417 ​ 1,600 Construction and land development ​ — ​ — ​ 8,525 ​ 8,525 ​ 10,906 Total ​ $ — ​ $ — ​ $ 13,037 ​ $ 13,037 ​ $ 15,988
Schedule of average investment in impaired loans and related interest income recognized	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 3,281 ​ $ 4 ​ $ 2 Commercial real estate ​ 1,329 ​ — ​ — Construction and land development ​ 8,338 ​ — ​ — Total impaired loans ​ $ 12,947 ​ $ 4 ​ $ 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 4,195 ​ $ — ​ $ 8 Multi-family residential ​ 74 ​ — ​ — Commercial real estate ​ 1,593 ​ — ​ — Construction and land development ​ 8,726 ​ — ​ — Consumer ​ 16 ​ — ​ — Total impaired loans ​ $ 14,604 ​ $ — ​ $ 8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 3,219 ​ $ 9 ​ $ 2 Commercial real estate ​ 1,358 ​ — ​ — Construction and land development ​ 8,400 ​ — ​ — Consumer ​ — ​ — ​ — Total impaired loans ​ $ 12,977 ​ $ 9 ​ $ 2 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2020 ​ ​ Average ​ ​ ​ ​ Income ​ ​ Recorded ​ Income Recognized ​ Recognized on ​ Investment on Accrual Basis Cash Basis ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 4,195 ​ $ 3 ​ $ 17 Multi-family residential ​ 74 ​ — ​ — Commercial real estate ​ 1,593 ​ — ​ 1 Construction and land development ​ 8,725 ​ — ​ — Commercial business ​ 4 ​ — ​ 1 Consumer ​ 16 ​ — ​ — Total impaired loans ​ $ 14,607 ​ $ 3 ​ $ 19 ​
Schedule of classes of the loan portfolio in which a formal risk weighting system is utilized	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ Special ​ ​ ​ ​ ​ ​ ​ ​ ​ Pass Mention Substandard Doubtful Total ​ ​ (Dollars in Thousands) One-to-four residential ​ $ 205,653 ​ $ 1,441 ​ $ 3,475 ​ $ — ​ $ 210,569 Multi-family residential ​ 52,657 ​ — ​ — ​ — ​ 52,657 Commercial real estate ​ 138,307 ​ 9,750 ​ 1,328 ​ — ​ 149,385 Construction and land development ​ 256,368 ​ — ​ 8,250 ​ — ​ 264,618 Commercial business ​ 41,882 ​ — ​ — ​ — ​ 41,882 Total ​ $ 694,867 ​ $ 11,191 ​ $ 13,053 ​ $ — ​ $ 719,111 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ Special ​ ​ ​ ​ ​ ​ ​ Pass Mention Substandard Doubtful Total ​ ​ (Dollars in Thousands) One-to-four residential ​ $ 229,361 ​ $ 1,416 ​ $ 3,095 ​ $ — ​ $ 233,872 Multi-family residential ​ 31,100 ​ — ​ — ​ — ​ 31,100 Commercial real estate ​ 128,527 ​ 9,999 ​ 1,417 ​ — ​ 139,943 Construction and land development ​ 252,123 ​ — ​ 8,525 ​ — ​ 260,648 Loans to financial institutions ​ ​ 6,000 ​ — ​ — ​ — ​ 6,000 Commercial business ​ 12,916 ​ — ​ — ​ — ​ 12,916 Total ​ $ 660,027 ​ $ 11,415 ​ $ 13,037 ​ $ — ​ $ 684,479 ​
Schedule of loans in which a formal risk rating system is not utilized, but loans are segregated between performing and non-performing based primarily on delinquency status	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Non- ​ ​ ​ Performing ​ Performing ​ Total ​ ​ (Dollars in Thousands) Leases ​ $ 117 ​ $ — ​ $ 117 Consumer ​ 515 ​ — ​ 515 Total ​ $ 632 ​ $ — ​ $ 632 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ Non- ​ ​ ​ Performing ​ Performing ​ Total ​ ​ (Dollars in Thousands) Leases ​ $ 176 ​ $ — ​ $ 176 Consumer ​ 604 ​ — ​ 604 Total ​ $ 780 ​ $ — ​ $ 780
Schedule of loan categories of the loan portfolio summarized by the aging categories of performing and delinquent loans and nonaccrual loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 90 Days+ ​ ​ ​ ​ ​ 30 ‑ 89 Days ​ 90 Days + ​ Total ​ Total ​ Non- ​ Past Due ​ ​ Current ​ Past Due ​ Past Due ​ Past Due ​ Loans ​ Accrual ​ and Accruing ​ ​ (Dollars in Thousands) One-to-four family residential $ 206,656 ​ $ 671 ​ $ 3,242 ​ $ 3,913 ​ $ 210,569 ​ $ 3,475 ​ $ — Multi-family residential ​ 52,657 ​ — ​ — ​ — ​ 52,657 ​ — ​ — Commercial real estate ​ 145,673 ​ 2,384 ​ 1,328 ​ 3,712 ​ 149,385 ​ 1,328 ​ — Construction and land development ​ 256,368 ​ — ​ 8,250 ​ 8,250 ​ 264,618 ​ 8,250 ​ — Commercial business ​ 41,882 ​ — ​ — ​ — ​ 41,882 ​ — ​ — Leases ​ 117 ​ — ​ — ​ — ​ 117 ​ — ​ Consumer ​ 458 ​ 57 ​ — ​ 57 ​ 515 ​ — ​ — Total Loans ​ $ 703,811 ​ $ 3,112 ​ $ 12,820 ​ $ 15,932 ​ $ 719,743 ​ $ 13,053 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 90 Days+ ​ ​ ​ ​ ​ 30 ‑ 89 Days ​ 90 Days + ​ Total ​ Total ​ Non- ​ Past Due ​ ​ Current ​ Past Due ​ Past Due ​ Past Due ​ Loans ​ Accrual ​ and Accruing ​ ​ (Dollars in Thousands) One-to-four family residential ​ $ 231,196 ​ $ 523 ​ $ 2,153 ​ $ 2,676 ​ $ 233,872 ​ $ 3,095 ​ $ — Multi-family residential ​ 31,100 ​ — ​ — ​ — ​ 31,100 ​ — ​ — Commercial real estate ​ 136,225 ​ 2,301 ​ 1,417 ​ 3,718 ​ 139,943 ​ 1,417 ​ — Construction and land development ​ 252,123 ​ — ​ 8,525 ​ 8,525 ​ 260,648 ​ 8,525 ​ — Commercial business ​ 12,916 ​ — ​ — ​ — ​ 12,916 ​ — ​ — Loans to financial institutions ​ ​ 6,000 ​ — ​ — ​ — ​ 6,000 ​ — ​ — Leases ​ 176 ​ — ​ — ​ — ​ 176 ​ — ​ Consumer ​ 604 ​ — ​ — ​ — ​ 604 ​ — ​ — Total Loans ​ $ 670,340 ​ $ 2,824 ​ $ 12,095 ​ $ 14,919 ​ $ 685,259 ​ $ 13,037 ​ $ — ​
Schedule of primary segments of the allowance for loan losses, segmented into the amount required for loans individually evaluated for impairment and the amount required for loans collectively evaluated for impairment.	The following tables summarize the primary segments of the allowance for loan losses. Activity in the allowance is presented for both the three and six month periods ended March 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2021 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ALLL balance at December 31, 2020 ​ $ 2,011 ​ $ 457 ​ $ 1,935 ​ $ 2,828 ​ $ 319 ​ $ — ​ $ 3 ​ $ 6 ​ $ 759 ​ $ 8,318 Charge-offs ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Recoveries ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 35 ​ ​ — ​ ​ 35 Provision ​ ​ (428) ​ ​ 263 ​ ​ 34 ​ ​ (118) ​ ​ 261 ​ ​ — ​ ​ — ​ ​ (36) ​ ​ 24 ​ ​ — ALLL balance at March 31, 2021 ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ 580 ​ $ — ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2021 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ALLL balance at September 30, 2020 ​ $ 1,877 ​ $ 460 ​ $ 1,989 ​ $ 2,888 ​ $ 194 ​ $ 89 ​ $ 3 ​ $ 6 ​ $ 797 ​ $ 8,303 Charge-offs ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Recoveries ​ ​ 1 ​ ​ — ​ ​ — ​ ​ — ​ ​ 14 ​ ​ — ​ ​ — ​ ​ 35 ​ ​ — ​ ​ 50 Provision ​ ​ (295) ​ ​ 260 ​ ​ (20) ​ ​ (178) ​ ​ 372 ​ ​ (89) ​ ​ — ​ ​ (36) ​ ​ (14) ​ ​ — ALLL balance at March 31, 2021 ​ $ 1,583 ​ $ 720 ​ $ 1,969 ​ $ 2,710 ​ $ 580 ​ $ — ​ $ 3 ​ $ 5 ​ $ 783 ​ $ 8,353 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ​ ​ ​ ALLL balance at December 31, 2019 ​ $ 999 ​ $ 255 ​ $ 1,281 ​ $ 2,205 ​ $ 201 ​ $ 63 ​ $ 4 ​ $ 12 ​ $ 508 ​ $ 5,528 Charge-offs ​ ​ (3) ​ ​ - ​ ​ - ​ ​ - ​ ​ (15) ​ ​ — ​ ​ — ​ ​ (56) ​ ​ — ​ ​ (74) Recoveries ​ ​ 1 ​ ​ - ​ ​ - ​ ​ - ​ ​ - ​ ​ — ​ ​ — ​ ​ 6 ​ ​ — ​ ​ 7 Provision ​ ​ 304 ​ ​ 40 ​ ​ 84 ​ ​ -115 ​ ​ 71 ​ ​ 7 ​ ​ — ​ ​ 41 ​ ​ 68 ​ ​ 500 ALLL balance at March 31, 2020 ​ $ 1,301 ​ $ 295 ​ $ 1,365 ​ $ 2,090 ​ $ 257 ​ $ 70 ​ $ 4 ​ $ 3 ​ $ 576 ​ $ 5,961 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended March 31, 2020 ​ One- to Multi- ​ ​ Construction ​ ​ Loans to ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ four-family ​ family ​ Commercial ​ and land ​ Commercial ​ financial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ residential ​ residential ​ real estate ​ development ​ business ​ institutions ​ Leases ​ Consumer ​ Unallocated ​ Total ​ ​ (In Thousands) ​ ​ ​ ALLL balance at September 30, 2019 ​ $ 1,002 ​ $ 315 ​ $ 1,257 ​ $ 2,034 ​ $ 206 ​ $ 63 ​ $ 5 ​ $ 13 ​ $ 498 ​ $ 5,393 Charge-offs ​ ​ (3) ​ ​ — ​ ​ — ​ ​ — ​ ​ (15) ​ ​ — ​ ​ — ​ ​ (56) ​ ​ — ​ ​ (74) Recoveries ​ ​ 1 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 10 ​ ​ 6 ​ ​ — ​ ​ 17 Provision ​ ​ 301 ​ ​ (20) ​ ​ 108 ​ ​ 56 ​ ​ 66 ​ ​ 7 ​ ​ (11) ​ ​ 40 ​ ​ 78 ​ ​ 625 ALLL balance at March 31, 2020 ​ $ 1,301 ​ $ 295 ​ $ 1,365 ​ $ 2,090 ​ $ 257 ​ $ 70 ​ $ 4 ​ $ 3 ​ $ 576 ​ $ 5,961

DEPOSITS (Tables)

DEPOSITS (Tables)	6 Months Ended
	Mar. 31, 2021
DEPOSITS [Abstract]
Schedule of major classifications of deposits	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ ​ 2021 ​ 2020 ​ ​ Amount Percent Amount Percent ​ ​ ​ (Dollars in Thousands) ​ Non-interest-bearing checking accounts ​ $ 32,253 4.1 % $ 30,002 3.9 % ​ Interest-bearing checking accounts ​ 112,752 14.2 % 135,797 17.6 % ​ Money market deposit accounts ​ 116,882 14.7 % 111,105 14.4 % ​ Passbook, club and statement savings ​ 229,936 29.0 % 224,435 29.1 % ​ Certificates maturing in six months or less ​ 162,045 20.4 % 125,165 16.2 % ​ Certificates maturing in more than six months ​ 139,877 17.6 % 144,445 18.8 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 793,745 100.0 % $ 770,949 100.0 % ​

ADVANCES FROM FEDERAL HOME LO_3

ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM (Tables)	6 Months Ended
	Mar. 31, 2021
ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM
Schedule of short-term borrowings from the FHLB of Pittsburgh	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, September 30, ​ (Dollar Amounts in Thousands) 2021 2020 ​ Balance at year-end ​ $ — ​ $ 25,000 ​ ​ Weight-average rate at period-end ​ — % 0.39 % ​ ​

ADVANCES FROM FEDERAL HOME LO_4

ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM (Tables)	6 Months Ended
	Mar. 31, 2021
ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM
Schedule of collateral agreement with the FHLB	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Lomg-term FHLB advances: ​ Maturity range ​ Weighted average ​ Stated interest rate range ​ March 31, ​ September 30, Description from to interest rate from to 2021 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in Thousands) Fixed Rate - Amortizing 1 ‑ Oct ‑ 20 30 ‑ Sep ‑ 21 ​ 2.80 % 2.72 % 2.83 % $ 1,074 ​ $ 5,179 Fixed Rate - Amortizing 1 ‑ Oct ‑ 21 30 ‑ Sep ‑ 22 ​ 2.88 % 1.99 % 3.05 % 3,886 ​ 5,523 Fixed Rate - Amortizing 1 ‑ Oct ‑ 22 30 ‑ Sep ‑ 23 ​ 2.89 % 1.94 % 3.11 % 4,414 ​ 5,265 Total ​ 2.87 % ​ ​ 9,374 ​ ​ 15,967 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Rate - Advances 1 ‑ Oct ‑ 20 30 ‑ Sep ‑ 21 ​ 2.30 % 1.42 % 2.35 % ​ 15,996 ​ ​ 17,996 Fixed Rate - Advances 1 ‑ Oct ‑ 21 30 ‑ Sep ‑ 22 ​ 2.31 % 1.94 % 3.23 % 63,272 ​ 63,293 Fixed Rate - Advances 1 ‑ Oct ‑ 22 30 ‑ Sep ‑ 23 ​ 2.52 % 2.00 % 3.22 % 94,999 ​ 94,999 Fixed Rate - Advances 1 ‑ Oct ‑ 23 30 ‑ Sep ‑ 24 ​ 2.88 % 2.38 % 3.20 % 67,998 ​ 67,998 Total ​ 2.55 % ​ ​ 242,265 ​ ​ 244,286 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2.57 % ​ Total ​ $ 251,639 ​ $ 260,253

INTEREST RATE SWAPS (Tables)

INTEREST RATE SWAPS (Tables)	6 Months Ended
	Mar. 31, 2021
INTEREST RATE SWAPS
Schedule of interest rate swap agreements and the terms	Below is a summary of the interest rate swap agreements and their terms as of March 31, 2021. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 Hedged ​ Notional ​ Pay Rate ​ Receive ​ Maturity Date ​ Unrealized Item Amount from to Rate from to ​ Loss (Dollars in Thousands) State and political subdivisions ​ $ 21,570 ​ 3.06 % 3.07 % 3 Mth Libor ​ 1-Feb-27 ​ 1-May-28 ​ $ (2,316) Commercial loans ​ 23,656 4.10 % 5.74 % 1 Mth Libor +225 to 276 bp ​ 13-Jun-25 ​ 1-Aug-26 ​ — 30 day wholesale funding ​ ​ 90,000 ​ 1.36 % 2.70 % 1 Mth Libor ​ 15-Feb-24 ​ 12-Jun-26 ​ ​ (4,099) 90 day wholesale funding ​ ​ 135,000 ​ 2.51 % 2.78 % 3 Mth Libor ​ 11-Jan-24 ​ 27-Mar-24 ​ ​ (8,466) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (14,881) ​ Below is a summary of the interest rate swap agreements and their terms as of September 30, 2020. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 Hedged ​ Notional ​ Pay Rate ​ Receive ​ Maturity Date ​ Unrealized Item Amount from to Rate from to Loss (Dollars in T housands) State and political subdivisions ​ $ 21,570 ​ 3.06 % 3.07 % 3 Mth Libor ​ 1-Feb-27 ​ 1-May-28 ​ $ (3,834) Commercial loans ​ 23,656 4.10 % 5.74 % 1 Mth Libor +225 to 276 bp ​ 13-Jun-25 ​ 1-Aug-26 ​ — 30 day wholesale funding ​ ​ 90,000 ​ 1.36 % 2.70 % 1 Mth Libor ​ 15-Feb-24 ​ 12-Jun-26 ​ ​ (6,157) 90 day wholesale funding ​ ​ 135,000 ​ 2.51 % 2.78 % 3 Mth Libor ​ 11-Jan-24 ​ 27-Mar-24 ​ ​ (10,969) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ (20,960)

INCOME TAXES (Tables)

INCOME TAXES (Tables)	6 Months Ended
	Mar. 31, 2021
INCOME TAXES
Schedule of deferred income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ September 30, ​ ​ 2021 2020 ​ ​ ​ (Dollars in Thousands) ​ Deferred tax assets: ​ ​ ​ Allowance for loan losses ​ $ 2,074 ​ $ 2,071 ​ Nonaccrual interest ​ 625 ​ 561 ​ Accrued vacation ​ 16 ​ 16 ​ Capital loss carryforward ​ 4 ​ 4 ​ Split dollar life insurance ​ 9 ​ 9 ​ Post-retirement benefits ​ 70 ​ 72 ​ Realized loss on equity securities ​ — ​ 3 ​ Unrealized losses on interest rate swaps ​ ​ 2,637 ​ ​ 3,596 ​ Deferred compensation ​ 756 ​ 781 ​ Goodwill ​ 52 ​ 58 ​ Lease liability ​ ​ 276 ​ ​ — ​ Other ​ 104 ​ 48 ​ Employee benefit plans ​ 214 ​ 187 ​ Total deferred tax assets ​ 6,837 ​ 7,406 ​ Valuation allowance ​ (4) ​ (4) ​ Total deferred tax assets, net of valuation allowance ​ 6,833 ​ 7,402 ​ ​ ​ ​ ​ Deferred tax liabilities: ​ ​ ​ Property ​ 173 ​ 137 ​ Right of Use ​ ​ 251 ​ ​ — ​ Realized gain on equity securities ​ ​ 9 ​ ​ — ​ Unrealized gains on available for sale securities ​ ​ 2,227 ​ ​ 2,813 ​ Purchase accounting adjustments ​ 359 ​ 321 ​ Deferred loan fees ​ 401 ​ 229 ​ Total deferred tax liabilities ​ 3,420 ​ 3,500 ​ Net deferred tax assets ​ $ 3,413 ​ $ 3,902 ​

STOCK COMPENSATION PLANS (Table

STOCK COMPENSATION PLANS (Tables)	6 Months Ended
	Mar. 31, 2021
STOCK COMPENSATION PLANS
Schedule of summary of the non-vested stock award activity	​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ March 31, 2021 ​ ​ Number of ​ Weighted Average ​ Shares Grant Date Fair Value Non-vested stock awards at October 1, 2020 23,056 ​ $ 17.78 Granted — ​ — Forfeited — ​ — Vested (8,128) ​ 18.03 Non-vested stock awards at March 31, 2021 14,928 ​ $ 17.66 ​
Schedule of summary of the status of the company' stock options under the stock option plan	​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ March 31, 2021 ​ Number of Weighted Average ​ ​ Shares ​ Exercise Price Options outstanding at October 1, 2020 571,258 ​ $ 14.58 Granted — ​ — Exercised (15,000) ​ 12.23 Forfeited (39,500) ​ 18.42 Outstanding at March 31, 2021 516,758 ​ $ 14.36 Exercisable at March 31, 2021 400,231 ​ $ 13.70 ​

FAIR VALUE MEASUREMENT (Tables)

FAIR VALUE MEASUREMENT (Tables)	6 Months Ended
	Mar. 31, 2021
FAIR VALUE MEASUREMENT
Schedule of assets measured at fair value on recurring basis	Those assets and liabilities as of March 31, 2021 which are measured at fair value on a recurring basis are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Category Used for Fair Value Measurement ​ Level 1 Level 2 Level 3 Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ ​ Securities available for sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government and agency obligations ​ $ — ​ $ 10,893 ​ $ — ​ $ 10,893 State and political subdivisions ​ — ​ 79,351 ​ — ​ 79,351 Mortgage-backed securities - U.S. Government agencies ​ — ​ 179,701 ​ — ​ 179,701 Corporate bonds ​ — ​ 83,862 ​ — ​ 83,862 Equity securities ​ 54 ​ — ​ — ​ 54 Total ​ $ 54 ​ $ 353,807 ​ $ — ​ $ 353,861 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap contracts ​ $ — ​ $ 14,881 ​ $ — ​ $ 14,881 Total ​ $ — ​ $ 14,881 ​ $ — ​ $ 14,881 ​ Those assets and liabilities as of September 30, 2020 which are measured at fair value on a recurring basis are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Category Used for Fair Value Measurement ​ Level 1 Level 2 Level 3 Total ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets: ​ ​ ​ ​ ​ ​ ​ ​ Securities available for sale: ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government and agency obligations ​ $ — ​ $ 22,394 ​ $ — ​ $ 22,394 State and political subdivisions ​ ​ — ​ 79,621 ​ — ​ 79,621 Mortgage-backed securities - U.S. Government agencies ​ — ​ 236,566 ​ — ​ 236,566 Corporate bonds ​ — ​ 81,783 ​ — ​ 81,783 Equity securities ​ 51 ​ — ​ — ​ 51 Total ​ $ 51 ​ $ 420,364 ​ $ — ​ $ 420,415 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate swap contracts ​ $ — ​ $ 20,960 ​ $ — ​ $ 20,960 Total ​ $ — ​ $ 20,960 ​ $ — ​ $ 20,960 ​
Schedule of the estimated fair value amounts	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements at ​ ​ Carrying ​ Fair ​ March 31, 2021 ​ Amount Value (Level 1) (Level 2) (Level 3) ​ ​ (Dollars in Thousands) ​ ​ ​ Assets: ​ ​ ​ ​ ​ Investment and mortgage-backed securities held to maturity ​ $ 22,270 ​ $ 23,460 ​ $ — ​ $ 23,460 ​ $ — Loans receivable, net ​ ​ 620,875 ​ ​ 622,637 ​ ​ — ​ ​ — ​ ​ 622,637 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Certificates of deposit ​ ​ 301,922 ​ ​ 311,058 ​ ​ 311,058 ​ ​ — ​ ​ — Advances from FHLB - long-term ​ ​ 251,639 ​ ​ 261,171 ​ ​ 261,171 ​ ​ — ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements at ​ ​ Carrying ​ Fair ​ September 30, 2020 ​ Amount Value (Level 1) (Level 2) (Level 3) ​ ​ (Dollars in Thousands) ​ ​ ​ Assets: ​ ​ ​ ​ ​ Investment and mortgage-backed securities held to maturity ​ $ 22,860 ​ $ 24,330 ​ $ — ​ $ 24,330 ​ $ — Loans receivable, net ​ ​ 588,300 ​ ​ 593,768 ​ ​ ​ ​ ​ ​ ​ ​ 593,768 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Certificates of deposit ​ ​ 269,610 ​ ​ 278,224 ​ ​ 278,224 ​ ​ — ​ ​ — Advances from FHLB - long-term ​ ​ 260,253 ​ ​ 274,172 ​ ​ 274,172 ​ ​ — ​ ​ —

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	6 Months Ended
	Mar. 31, 2021
GOODWILL AND OTHER INTANGIBLE ASSETS
Schedule of goodwill and intangible assets are related to the acquisition of Polonia Bancorp	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ ​ ​ ​ Balance ​ ​ ​ ​ October 1, ​ Additions/ ​ ​ ​ ​ March 31, ​ Amortization ​ 2020 Adjustments Amortization 2021 Period ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in Thousands) ​ ​ Goodwill ​ $ 6,102 ​ $ — ​ $ — ​ $ 6,102 Core deposit intangible ​ 340 ​ — ​ (49) ​ 291 10 years ​ ​ $ 6,442 ​ $ — ​ $ (49) ​ $ 6,393
Schedule of future fiscal periods amortization expense for core deposit intangible	​ ​ ​ ​ ​ (in Thousands) ​ ​ ​ ​ ​ ​ 2021 ​ $ 44 2022 ​ 78 2023 ​ 64 2024 ​ 49 2025 ​ 34 Thereafter ​ 22 ​ ​ $ 291

LEASES (Tables)

LEASES (Tables)	6 Months Ended
	Mar. 31, 2021
LEASES [Abstract]
Schedule of information related to operating leases	The following table summarizes other information related to our operating leases: ​ ​ ​ ​ ​ March 31, 2021 ​ ​ Weighted-average remaining lease term - operating leases in years 6.85 ​ Weighted-average discount rate - operating leases 2.0 %
Schedule of aggregate lease maturities and obligations	The following table presents aggregate lease maturities and obligations as of March 31, 2021: ​ ​ ​ ​ ​ (Dollars in Thousands) ​ ​ ​ ​ ​ ​ 2021 ​ $ 105 2022 ​ 213 2023 ​ 216 2024 ​ 220 2025 ​ 231 2025 and thereafter ​ ​ 423 Total lease payments ​ ​ 1,408 Less: interest ​ 96 Present value of lease liabilities ​ $ 1,312

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	6 Months Ended
	Mar. 31, 2021USD ($)item	Sep. 30, 2020USD ($)
Significant Accounting Policies [Line Items]
Number of full service branch offices	9
Number of banking offices	10
Operating right-of-use assets | $	$ 1,200
Operating lease liabilities | $	1,312
Retained earnings | $	$ 55,313	$ 52,889
Philadelphia (Philadelphia County)
Significant Accounting Policies [Line Items]
Number of full service branch offices	8
PENNSYLVANIA
Significant Accounting Policies [Line Items]
Number of full service branch offices	1
Huntingdon Valley, Montgomery County
Significant Accounting Policies [Line Items]
Number of full service branch offices	1

EARNINGS PER SHARE - Calculated

EARNINGS PER SHARE - Calculated basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Earnings per share - basic
Net income	$ 1,715	$ 2,924	$ 3,551	$ 5,387
Weighted average common shares outstanding - basic	7,975,683	8,884,760	8,040,907	8,885,972
Effect of CSEs - basic	0	0
Adjusted weighted average common shares used in earnings per share computation - basic	7,975,683	8,884,760	8,040,907	8,885,972
Earnings per share - basic (in dollars per share)	$ 0.22	$ 0.33	$ 0.44	$ 0.61
Earnings per share - diluted
Net income	$ 1,715	$ 2,924	$ 3,551	$ 5,387
Weighted average shares outstanding - diluted	7,975,683	8,884,760	8,040,907	8,885,972
Effect of CSEs - diluted	14,671	117,342	4,512	133,815
Adjusted weighted average shares used in earnings per share computation - diluted	7,990,354	9,002,102	8,045,419	9,019,787
Earnings per share - diluted (in dollars per share)	$ 0.21	$ 0.32	$ 0.44	$ 0.60

EARNINGS PER SHARE - Additional

EARNINGS PER SHARE - Additional Information (Details) - shares	Mar. 31, 2021	Mar. 31, 2020
EARNINGS PER SHARE
Adjusted weighted average shares of common stock used in diluted earnings per share computation	267,728	528,004
Adjusted weighted average shares of common stock having exercise prices less than the current market value and are considered anti-dilutive	249,030	265,030

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Changes in accumulated other comprehensive (loss) income by component net of tax (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance			$ (2,943)
Total other comprehensive (loss) gain	$ (1,342)	$ (6,678)	1,394	$ (6,045)
Ending Balance	(1,549)		(1,549)
Total accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(207)	1,824	(2,943)	1,192
Other comprehensive (loss) income before reclassification	(1,342)	(4,809)	1,394	(3,926)
Total other comprehensive (loss) gain	(1,549)	(2,985)	(1,549)	(2,734)
Amount reclassified from accumulated other comprehensive income	0	(1,868)		(2,119)
Ending Balance	(1,549)	(4,853)	(1,549)	(4,853)
Unrealized gain (loss) on AFS securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	12,221		10,585	8,098
Other comprehensive (loss) income before reclassification	(3,842)		(2,206)	2,885
Total other comprehensive (loss) gain	8,379		8,379	10,983
Amount reclassified from accumulated other comprehensive income	0			(2,119)
Ending Balance	8,379	8,864	8,379	8,864
Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(12,428)
Other comprehensive (loss) income before reclassification	2,500
Total other comprehensive (loss) gain	(9,928)
Amount reclassified from accumulated other comprehensive income	0
Ending Balance	(9,928)		(9,928)
Unrealized gains on available for sale securities and interest rate swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		(5,096)	(13,528)	(6,906)
Other comprehensive (loss) income before reclassification		(8,621)	3,600	(6,811)
Total other comprehensive (loss) gain		(13,717)	(9,928)	(13,717)
Amount reclassified from accumulated other comprehensive income		0
Ending Balance	$ (9,928)	(13,717)	$ (9,928)	(13,717)
Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		6,920
Other comprehensive (loss) income before reclassification		3,812
Total other comprehensive (loss) gain		10,732
Amount reclassified from accumulated other comprehensive income		(1,868)
Ending Balance		$ 8,864		$ 8,864

INVESTMENT AND MORTGAGE-BACKE_3

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Amortized cost and fair value of investment and mortgage-backed securities, with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Securities Available for Sale:
Amortized Cost	$ 343,200
Gross Unrealized Gains	12,366
Gross Unrealized Losses	(1,759)
Fair Value	353,807	$ 420,364
U.S. Government and agency obligations
Securities Available for Sale:
Amortized Cost	10,811	22,241
Gross Unrealized Gains	82	153
Gross Unrealized Losses	0
Fair Value	10,893	22,394
State and political subdivisions
Securities Available for Sale:
Amortized Cost	77,437	79,099
Gross Unrealized Gains	2,560	1,940
Gross Unrealized Losses	(646)	(1,418)
Fair Value	79,351	79,621
Mortgage-Backed Securities
Securities Available for Sale:
Amortized Cost	174,243	226,863
Gross Unrealized Gains	6,387	9,774
Gross Unrealized Losses	(929)	(71)
Fair Value	179,701	236,566
Corporate debt securities
Securities Available for Sale:
Amortized Cost	80,709	78,764
Gross Unrealized Gains	3,337	3,564
Gross Unrealized Losses	(184)	(545)
Fair Value	$ 83,862	81,783
Total debt securities available for sale
Securities Available for Sale:
Amortized Cost		406,967
Gross Unrealized Gains		15,431
Gross Unrealized Losses		(2,034)
Fair Value		$ 420,364

INVESTMENT AND MORTGAGE-BACKE_4

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Amortized cost and fair value of investment and mortgage-backed securities, with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Securities Held to Maturity:
Amortized Cost	$ 22,270	$ 22,860
Gross Unrealized Gains	1,190	1,470
Gross unrealized losses	0
Fair value	23,460	24,330
U.S. Government and agency obligations
Securities Held to Maturity:
Amortized Cost	1,000	1,000
Gross Unrealized Gains	185	236
Gross unrealized losses	0
Fair value	1,185	1,236
Mortgage-Backed Securities
Securities Held to Maturity:
Amortized Cost	3,248	3,784
Gross Unrealized Gains	267	309
Gross unrealized losses	0
Fair value	3,515	4,093
State and political subdivisions
Securities Held to Maturity:
Amortized Cost	18,022	18,076
Gross Unrealized Gains	738	925
Gross unrealized losses	0
Fair value	$ 18,760	$ 19,001

INVESTMENT AND MORTGAGE-BACKE_5

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Gross unrealized losses and related fair values of investment securities, aggregated by investment category and length of time (Details) - USD ($)	Mar. 31, 2021	Sep. 30, 2020
Securities Available for Sale:
Less than 12 months - Gross Unrealized Losses	$ (1,249,000)	$ (737,000)
Less than 12 months - Fair value	48,279,000	37,232,000
More than 12 months - Gross Unrealized Losses	(510,000)	(1,297,000)
More than 12 months - Fair value	6,838,000	25,094,000
Gross Unrealized Losses - Total	(1,759,000)	(2,034,000)
Fair Value - Total	55,117,000	62,326,000
State and political subdivisions
Securities Available for Sale:
Less than 12 months - Gross Unrealized Losses	(136,000)	(126,000)
Less than 12 months - Fair value	10,686,000	10,735,000
More than 12 months - Gross Unrealized Losses	(510,000)	(1,292,000)
More than 12 months - Fair value	6,838,000	24,510,000
Gross Unrealized Losses - Total	(646,000)	(1,418,000)
Fair Value - Total	17,524,000	35,245,000
Mortgage-Backed Securities
Securities Available for Sale:
Less than 12 months - Gross Unrealized Losses	(929,000)	(66,000)
Less than 12 months - Fair value	25,777,000	10,025,000
More than 12 months - Gross Unrealized Losses		(5,000)
More than 12 months - Fair value		584,000
Gross Unrealized Losses - Total	(929,000)	(71,000)
Fair Value - Total	25,777,000	10,609,000
Corporate debt securities
Securities Available for Sale:
Less than 12 months - Gross Unrealized Losses	(184,000)	(545,000)
Less than 12 months - Fair value	11,816,000	16,472,000
Gross Unrealized Losses - Total	(184,000)	(545,000)
Fair Value - Total	$ 11,816,000	$ 16,472,000

INVESTMENT AND MORTGAGE-BACKE_6

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Amortized cost and fair value of debt securities, by contractual maturity (Details) $ in Thousands	Mar. 31, 2021USD ($)
Available for Sale, Amortized Cost
Due after one through five years	$ 31,190
Due after five through ten years	50,705
Due after ten years	87,062
Total	168,957
Available for Sale, Fair Value
Due after one through five years	32,832
Due after five through ten years	52,297
Due after ten years	88,977
Total	$ 174,106

INVESTMENT AND MORTGAGE-BACKE_7

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Amortized cost and fair value of debt securities, by contractual maturity (Details) $ in Thousands	Mar. 31, 2021USD ($)
Held to Maturity - Amortized Cost
Due after one through five years	$ 5,693
Due after five through ten years	9,284
Due after ten years	4,045
Total	19,022
Held to Maturity - Fair Value
Due after one through five years	6,085
Due after five through ten years	9,594
Due after ten years	4,266
Total	$ 19,945

INVESTMENT AND MORTGAGE-BACKE_8

INVESTMENT AND MORTGAGE-BACKED SECURITIES - Additional Information (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2021USD ($)security	Mar. 31, 2020USD ($)	Mar. 31, 2021USD ($)security	Mar. 31, 2020USD ($)	Sep. 30, 2020USD ($)
Marketable Securities [Line Items]
Gain on sale of mortgage-backed securities available for sale		$ 2,364,000		$ 2,682,000
Securities with a fair value in safekeeping account at the FHLB	$ 151,500,000		$ 151,500,000
Aggregate Amount	1,249,000		1,249,000		$ 737,000
Gain (loss) on equity securities	(7,000)	(39,000)	3,000	(58,000)
Realized net gains (losses)		2,400,000		2,700,000
Proceeds from sale of investment and mortgage-backed securities				81,953,000
Required to hold securities for its borrowings	39,000,000		39,000,000
Excess securities not restricted and could be sold or transferred	112,500,000		112,500,000
Gross unrealized loss	$ 1,759,000		$ 1,759,000		2,034,000
Mortgage-back securities sold with an aggregate amortized cost		$ 44,600,000		$ 62,100,000
Mortgage-Backed Securities
Marketable Securities [Line Items]
Number of investment securities in debt obligations in the category of loss position less than 12 months held by company | security	15		15
Number of investment securities in debt obligations in the category of loss position more than 12 months held by company | security	0		0
Aggregate Amount	$ 929,000		$ 929,000		66,000
Gross unrealized loss	$ 929,000		$ 929,000		71,000
Corporate debt securities
Marketable Securities [Line Items]
Number of investment securities in debt obligations in the category of loss position less than 12 months held by company | security	3		3
Number of investment securities in debt obligations in the category of loss position more than 12 months held by company | security	0		0
Aggregate Amount	$ 184,000		$ 184,000		545,000
Gross unrealized loss	$ 184,000		$ 184,000		545,000
State and political subdivisions
Marketable Securities [Line Items]
Number of investment securities in debt obligations in the category of loss position less than 12 months held by company | security	4		4
Number of investment securities in debt obligations in the category of loss position more than 12 months held by company | security	3		3
Aggregate Amount	$ 136,000		$ 136,000		126,000
Gross unrealized loss	$ 646,000		$ 646,000		$ 1,418,000

LOANS RECEIVABLE (Details)

LOANS RECEIVABLE (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 719,743		$ 685,259
Undisbursed portion of loans-in-process	(89,912)		(86,862)
Deferred loan fees	(603)		(1,794)
Allowance for loan losses	(8,353)	$ (8,318)	(8,303)	$ (5,961)	$ (5,528)	$ (5,393)
Net loans	620,875		588,300
One-to-four family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	210,569		233,872
Allowance for loan losses	(1,583)	(2,011)	(1,877)	(1,301)	(999)	(1,002)
Multi Family Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	52,657		31,100
Allowance for loan losses	(720)	(457)	(460)	(295)	(255)	(315)
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	149,385		139,943
Allowance for loan losses	(1,969)	(1,935)	(1,989)	(1,365)	(1,281)	(1,257)
Construction and Land Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	264,618		260,648
Allowance for loan losses	(2,710)	(2,828)	(2,888)	(2,090)	(2,205)	(2,034)
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	41,882		12,916
Allowance for loan losses	(580)	(319)	(194)	(257)	(201)	(206)
Financial institutions
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans			6,000
Allowance for loan losses			(89)	(70)	(63)	(63)
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	117		176
Allowance for loan losses	(3)	(3)	(3)	(4)	(4)	(5)
Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	515		604
Allowance for loan losses	$ (5)	$ (6)	$ (6)	$ (3)	$ (12)	$ (13)

LOANS RECEIVABLE - Summary of l

LOANS RECEIVABLE - Summary of loans individually and collectively evaluated for impairment by loan segment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019
Loans:
Individually evaluated for impairment	$ 13,053		$ 13,037
Collectively evaluated for impairment	706,690		672,222
Total loans	719,743		685,259
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	8,353		8,303
Total ending allowance balance	8,353	$ 8,318	8,303	$ 5,961	$ 5,528	$ 5,393
One-to-four family residential
Loans:
Individually evaluated for impairment	3,475		3,095
Collectively evaluated for impairment	207,094		230,777
Total loans	210,569		233,872
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,583		1,877
Total ending allowance balance	1,583	2,011	1,877	1,301	999	1,002
Multi Family Residential
Loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	52,657		31,100
Total loans	52,657		31,100
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	720		460
Total ending allowance balance	720	457	460	295	255	315
Commercial Real Estate
Loans:
Individually evaluated for impairment	1,328		1,417
Collectively evaluated for impairment	148,057		138,526
Total loans	149,385		139,943
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,969		1,989
Total ending allowance balance	1,969	1,935	1,989	1,365	1,281	1,257
Construction and Land Development
Loans:
Individually evaluated for impairment	8,250		8,525
Collectively evaluated for impairment	256,368		252,123
Total loans	264,618		260,648
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,710		2,888
Total ending allowance balance	2,710	2,828	2,888	2,090	2,205	2,034
Financial institutions
Loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	0		6,000
Total loans			6,000
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	0		89
Total ending allowance balance			89	70	63	63
Commercial loans
Loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	41,882		12,916
Total loans	41,882		12,916
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	580		194
Total ending allowance balance	580	319	194	257	201	206
Leases
Loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	117		176
Total loans	117		176
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3		3
Total ending allowance balance	3	3	3	4	4	5
Consumer Loans
Loans:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	515		604
Total loans	515		604
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	5		6
Total ending allowance balance	5	6	6	3	12	13
Unallocated
Loans:
Collectively evaluated for impairment	783		797
Total ending allowance balance	$ 783	$ 759	$ 797	$ 576	$ 508	$ 498

LOANS RECEIVABLE - Impaired loa

LOANS RECEIVABLE - Impaired loans by class, segregated by those for which specific allowance was required and those for which specific allowance was not necessary (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Financing Receivable, Impaired [Line Items]
Impaired Loans with Specific Allowance - Recorded Investment	$ 0	$ 0
Impaired Loans with Specific Allowance - Related Allowance	0	0
Impaired Loans with No Specific Allowance - Recorded Investment	13,053	13,037
Total Impaired Loans - Recorded Investment	13,053	13,037
Total impaired loans - Unpaid Principal Balance	15,928	15,988
One-to-four family residential
Financing Receivable, Impaired [Line Items]
Impaired Loans with Specific Allowance - Recorded Investment	0	0
Impaired Loans with Specific Allowance - Related Allowance	0	0
Impaired Loans with No Specific Allowance - Recorded Investment	3,475	3,095
Total Impaired Loans - Recorded Investment	3,475	3,095
Total impaired loans - Unpaid Principal Balance	3,792	3,482
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Impaired Loans with Specific Allowance - Recorded Investment	0	0
Impaired Loans with Specific Allowance - Related Allowance	0	0
Impaired Loans with No Specific Allowance - Recorded Investment	1,328	1,417
Total Impaired Loans - Recorded Investment	1,328	1,417
Total impaired loans - Unpaid Principal Balance	1,505	1,600
Construction and Land Development
Financing Receivable, Impaired [Line Items]
Impaired Loans with Specific Allowance - Recorded Investment	0	0
Impaired Loans with Specific Allowance - Related Allowance	0	0
Impaired Loans with No Specific Allowance - Recorded Investment	8,250	8,525
Total Impaired Loans - Recorded Investment	8,250	8,525
Total impaired loans - Unpaid Principal Balance	$ 10,631	$ 10,906

LOANS RECEIVABLE - Average reco

LOANS RECEIVABLE - Average recorded investment in impaired loans and related interest income recognized (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 12,947	$ 14,604	$ 12,977	$ 14,607
Income Recognized on Accrual Basis	4	0	9	3
Income Recognized on Cash Basis	2	8	2	19
One-to-four family residential
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	3,281	4,195	3,219	4,195
Income Recognized on Accrual Basis	4	0	9	3
Income Recognized on Cash Basis	2	8	2	17
Multi Family Residential
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		74		74
Income Recognized on Accrual Basis		0
Income Recognized on Cash Basis		0
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,329	1,593	1,358	1,593
Income Recognized on Accrual Basis	0	0
Income Recognized on Cash Basis	0	0		1
Construction and Land Development
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	8,338	8,726	$ 8,400	8,725
Income Recognized on Accrual Basis	0	0
Income Recognized on Cash Basis	$ 0	0
Commercial loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment				4
Income Recognized on Cash Basis				1
Consumer Loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		16		$ 16
Income Recognized on Accrual Basis		0
Income Recognized on Cash Basis		$ 0

LOANS RECEIVABLE - Summary of c

LOANS RECEIVABLE - Summary of classes of loan portfolio in which formal risk weighting system is utilized (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 719,743	$ 685,259
One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	210,569	233,872
Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	52,657	31,100
Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	149,385	139,943
Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	264,618	260,648
Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		6,000
Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	41,882	12,916
Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	515	604
Risk Rating System
Financing Receivable, Recorded Investment [Line Items]
Total Loans	719,111	684,479
Risk Rating System | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	210,569	233,872
Risk Rating System | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	52,657	31,100
Risk Rating System | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	149,385	139,943
Risk Rating System | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	264,618	260,648
Risk Rating System | Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		6,000
Risk Rating System | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	41,882	12,916
Risk Rating System | Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans	694,867
Risk Rating System | Pass | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	205,653
Risk Rating System | Pass | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	52,657
Risk Rating System | Pass | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	138,307
Risk Rating System | Pass | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	256,368
Risk Rating System | Pass | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	41,882
Risk Rating System | Special Pass
Financing Receivable, Recorded Investment [Line Items]
Total Loans		660,027
Risk Rating System | Special Pass | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		229,361
Risk Rating System | Special Pass | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		31,100
Risk Rating System | Special Pass | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans		128,527
Risk Rating System | Special Pass | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans		252,123
Risk Rating System | Special Pass | Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		6,000
Risk Rating System | Special Pass | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans		12,916
Risk Rating System | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans	11,191
Risk Rating System | Special Mention | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,441
Risk Rating System | Special Mention | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	9,750
Risk Rating System | Total Mention
Financing Receivable, Recorded Investment [Line Items]
Total Loans		11,415
Risk Rating System | Total Mention | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		1,416
Risk Rating System | Total Mention | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Total Mention | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans		9,999
Risk Rating System | Total Mention | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Total Mention | Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Total Mention | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Loans	13,053	13,037
Risk Rating System | Substandard | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	3,475	3,095
Risk Rating System | Substandard | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Substandard | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans	1,328	1,417
Risk Rating System | Substandard | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 8,250	8,525
Risk Rating System | Substandard | Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Substandard | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | Multi Family Residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | Construction and Land Development
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | Financial institutions
Financing Receivable, Recorded Investment [Line Items]
Total Loans		0
Risk Rating System | Doubtful | Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans		$ 0

LOANS RECEIVABLE - Loans in whi

LOANS RECEIVABLE - Loans in which formal risk rating system is not utilized, but loans are segregated between performing and non-performing based primarily on delinquency status (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 719,743	$ 685,259
One-to-four family residential
Financing Receivable, Recorded Investment [Line Items]
Total Loans	210,569	233,872
Leases
Financing Receivable, Recorded Investment [Line Items]
Total Loans	117	176
Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	515	604
Non Risk Rating System
Financing Receivable, Recorded Investment [Line Items]
Total Loans	632	780
Non Risk Rating System | Leases
Financing Receivable, Recorded Investment [Line Items]
Total Loans	117	176
Non Risk Rating System | Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	515	604
Non Risk Rating System | Performing
Financing Receivable, Recorded Investment [Line Items]
Total Loans	632	780
Non Risk Rating System | Performing | Leases
Financing Receivable, Recorded Investment [Line Items]
Total Loans	117	176
Non Risk Rating System | Performing | Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	515	$ 604
Non Risk Rating System | Non-performing assets
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0
Non Risk Rating System | Non-performing assets | Leases
Financing Receivable, Recorded Investment [Line Items]
Total Loans	0
Non Risk Rating System | Non-performing assets | Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Total Loans	$ 0

LOANS RECEIVABLE - Loan categor

LOANS RECEIVABLE - Loan categories of loan portfolio summarized by aging categories of performing loans and nonaccrual loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 703,811	$ 670,340
Past Due	15,932	14,919
Total Loans	719,743	685,259
Non- Accrual	13,053	13,037
90 Days+ Past Due and Accruing	0	0
30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,112	2,824
Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	12,820	12,095
One-to-four family residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	206,656	231,196
Past Due	3,913	2,676
Total Loans	210,569	233,872
Non- Accrual	3,475	3,095
90 Days+ Past Due and Accruing	0	0
One-to-four family residential | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	671	523
One-to-four family residential | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,242	2,153
Multi Family Residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	52,657	31,100
Past Due	0	0
Total Loans	52,657	31,100
Non- Accrual	0	0
90 Days+ Past Due and Accruing	0	0
Multi Family Residential | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Multi Family Residential | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	145,673	136,225
Past Due	3,712	3,718
Total Loans	149,385	139,943
Non- Accrual	1,328	1,417
90 Days+ Past Due and Accruing	0	0
Commercial Real Estate | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,384	2,301
Commercial Real Estate | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,328	1,417
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	256,368	252,123
Past Due	8,250	8,525
Total Loans	264,618	260,648
Non- Accrual	8,250	8,525
90 Days+ Past Due and Accruing	0	0
Construction and Land Development | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Construction and Land Development | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	8,250	8,525
Commercial loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	41,882	12,916
Past Due	0	0
Total Loans	41,882	12,916
Non- Accrual	0	0
90 Days+ Past Due and Accruing	0	0
Commercial loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Commercial loans | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Financial institutions
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current		6,000
Past Due		0
Total Loans		6,000
Non- Accrual		0
90 Days+ Past Due and Accruing		0
Financial institutions | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0
Financial institutions | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0
Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	117	176
Past Due	0	0
Total Loans	117	176
Non- Accrual	0	0
Leases | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Leases | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	0	0
Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	458	604
Past Due	57	0
Total Loans	515	604
Non- Accrual	0	0
90 Days+ Past Due and Accruing	0	0
Consumer Loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	57	0
Consumer Loans | Over 90 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 0	$ 0

LOANS RECEIVABLE - Activity in

LOANS RECEIVABLE - Activity in allowance (Details) - USD ($)	3 Months Ended			6 Months Ended
	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	$ 8,318,000	$ 5,961,000	$ 5,528,000	$ 8,303,000	$ 5,393,000
Charge-offs			(74,000)		(74,000)
Recoveries	35,000		7,000	50,000	17,000
Provision	0	500,000	500,000	0	625,000
ALLL balance	8,353,000		5,961,000	8,353,000	5,961,000
Individually evaluated for impairment	0			0		$ 0
Collectively evaluated for impairment	8,353,000			8,353,000		8,303,000
One-to-four family residential
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	2,011,000	1,301,000	999,000	1,877,000	1,002,000
Charge-offs			(3,000)		(3,000)
Recoveries			1,000	1,000	1,000
Provision	(428,000)		304,000	(295,000)	301,000
ALLL balance	1,583,000		1,301,000	1,583,000	1,301,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	1,583,000			1,583,000		1,877,000
Multi Family Residential
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	457,000	295,000	255,000	460,000	315,000
Provision	263,000		40,000	260,000	(20,000)
ALLL balance	720,000		295,000	720,000	295,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	720,000			720,000		460,000
Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	1,935,000	1,365,000	1,281,000	1,989,000	1,257,000
Provision	34,000		84,000	(20,000)	108,000
ALLL balance	1,969,000		1,365,000	1,969,000	1,365,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	1,969,000			1,969,000		1,989,000
Construction and Land Development
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	2,828,000	2,090,000	2,205,000	2,888,000	2,034,000
Provision	(118,000)		(115,000)	(178,000)	56,000
ALLL balance	2,710,000		2,090,000	2,710,000	2,090,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	2,710,000			2,710,000		2,888,000
Commercial loans
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	319,000	257,000	201,000	194,000	206,000
Charge-offs			(15,000)		(15,000)
Recoveries				14,000
Provision	261,000		71,000	372,000	66,000
ALLL balance	580,000		257,000	580,000	257,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	580,000			580,000		194,000
Financial institutions
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance		70,000	63,000	89,000	63,000
Provision			7,000	(89,000)	7,000
ALLL balance			70,000		70,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	0			0		89,000
Leases
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	3,000	4,000	4,000	3,000	5,000
Recoveries					10,000
Provision					(11,000)
ALLL balance	3,000		4,000	3,000	4,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	3,000			3,000		3,000
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	6,000	3,000	12,000	6,000	13,000
Charge-offs			(56,000)		(56,000)
Recoveries	35,000		6,000	35,000	6,000
Provision	(36,000)		41,000	(36,000)	40,000
ALLL balance	5,000		3,000	5,000	3,000
Individually evaluated for impairment	0			0		0
Collectively evaluated for impairment	5,000			5,000		6,000
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
ALLL balance	759,000	$ 576,000	508,000	797,000	498,000
Provision	24,000		68,000	(14,000)	78,000
ALLL balance	783,000		$ 576,000	783,000	$ 576,000
Collectively evaluated for impairment	$ 783,000			$ 783,000		$ 797,000

LOANS RECEIVABLE - Additional I

LOANS RECEIVABLE - Additional Information 2 (Details)	3 Months Ended			6 Months Ended
	Mar. 31, 2021USD ($)loan	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)loan	Mar. 31, 2021USD ($)loan	Mar. 31, 2020USD ($)loan	Sep. 30, 2020USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans default | loan				4
Loans classified as troubled debt restructurings ("TDRs"), Recorded investment	$ 4,900,000			$ 4,900,000
Write-down amount of TDR loans			$ 74,000	$ 0	$ 74,000
Number of loans classified as troubled debt restructuring | loan	0		0	0	0
Loans receivable, net	$ 620,875,000			$ 620,875,000		$ 588,300,000
Charge-offs			$ 74,000		$ 74,000
Recoveries	35,000		7,000	50,000	17,000
Provision for loan losses	0	$ 500,000	$ 500,000	0	$ 625,000
Carrying amount	$ 719,743,000			$ 719,743,000		$ 685,259,000
Commercial and residential properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans classified as troubled debt restructuring | loan	0		0	0	0
Non-performing assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Write-down amount of TDR loans	$ 0
Recoveries	35,000
Non-performing assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans default | loan				3
Loans classified as troubled debt restructurings ("TDRs"), Recorded investment	4,500,000			$ 4,500,000
Amount of TDR loans, default				10,100,000
Non-performing assets | Single family residential investment properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans classified as troubled debt restructurings ("TDRs"), Recorded investment	$ 399,000			$ 399,000

DEPOSITS (Details)

DEPOSITS (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Amount
Non interest-bearing checking accounts	$ 32,253	$ 30,002
Interest-bearing checking accounts	112,752	135,797
Money market deposit accounts	116,882	111,105
Passbook, club and statement savings	229,936	224,435
Certificates maturing in six months or less	162,045	125,165
Certificates maturing in more than six months	139,877	144,445
Total deposits	$ 793,745	$ 770,949
Percent
Non interest-bearing checking accounts	4.10%	3.90%
Interest-bearing checking accounts	14.20%	17.60%
Money market deposit accounts	14.70%	14.40%
Passbook, club and statement savings	29.00%	29.10%
Certificates maturing in six months or less	20.40%	16.20%
Certificates maturing in more than six months	17.60%	18.80%
Total	100.00%	100.00%

DEPOSITS - Additional Informati

DEPOSITS - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Sep. 30, 2020
DEPOSITS [Abstract]
Certificates of $250,000 and over	$ 99.7	$ 76.6

ADVANCES FROM FEDERAL HOME LO_5

ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM (Details) $ in Thousands	Sep. 30, 2020USD ($)
ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM
Balance at period end	$ 25,000
Weight-average rate at period end	0.39%

ADVANCES FROM FEDERAL HOME LO_6

ADVANCES FROM FEDERAL HOME LOAN BANK - SHORT TERM - Additional Information (Details)	Mar. 31, 2021USD ($)loan	Sep. 30, 2020USD ($)
Short-term Debt [Line Items]
Advances from Federal Home Loan Bank - short term		$ 25,000,000
Unsecured borrowing facility, amount drawn	$ 0
Coupon	2.57%
Atlantic Community Bankers Bank [Member]
Short-term Debt [Line Items]
Unsecured borrowing facilities maximum capacity	$ 12,500,000
PNC [Member]
Short-term Debt [Line Items]
Unsecured borrowing facilities maximum capacity	$ 10,000,000
Interest rate swap contract one
Short-term Debt [Line Items]
Number of 90 day FHLB advances | loan	1
Advances from Federal Home Loan Bank - short term	$ 25,000,000

ADVANCES FROM FEDERAL HOME LO_7

ADVANCES FROM FEDERAL HOME LOAN BANK - LONG TERM (Details) - USD ($) $ in Thousands	18 Months Ended
	Mar. 31, 2021	Sep. 30, 2020
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.57%
Amount	$ 251,639	$ 260,253
Fixed Rate - Amortizing
Federal Home Loan Bank, Advances [Line Items]
Amount	$ 9,374	15,967
Weighted average interest rate	2.87%
Long-term FHLB advances
Federal Home Loan Bank, Advances [Line Items]
Amount	$ 242,265	244,286
Weighted average interest rate	2.55%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 20 to 30 Sep 21
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2020
Date of maturity to	Sep. 30, 2021
Amount	$ 1,074	5,179
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 20 to 30 Sep 21 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.72%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 20 to 30 Sep 21 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.83%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 20 to 30 Sep 21 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.80%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 21 to 30 Sep 22
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2021
Date of maturity to	Sep. 30, 2022
Amount	$ 3,886	5,523
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 21 to 30 Sep 22 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	1.99%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 21 to 30 Sep 22 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	3.05%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 21 to 30 Sep 22 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.88%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 22 to 30 Sep 23
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2022
Date of maturity to	Sep. 30, 2023
Amount	$ 4,414	5,265
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 22 to 30 Sep 23 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	1.94%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 22 to 30 Sep 23 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	3.11%
Long-term | Fixed Rate Amortizing Maturity from 1 Oct 22 to 30 Sep 23 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.89%
Long-term | Fixed Rate Advances Maturity from 1 Oct 20 to 30 Sep 21
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2020
Date of maturity to	Sep. 30, 2021
Amount	$ 15,996	17,996
Long-term | Fixed Rate Advances Maturity from 1 Oct 20 to 30 Sep 21 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	1.42%
Long-term | Fixed Rate Advances Maturity from 1 Oct 20 to 30 Sep 21 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.35%
Long-term | Fixed Rate Advances Maturity from 1 Oct 20 to 30 Sep 21 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.30%
Long-term | Fixed Rate Advances Maturity from 1 Oct 21 to 30 Sep 22
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2021
Date of maturity to	Sep. 30, 2022
Amount	$ 63,272	63,293
Long-term | Fixed Rate Advances Maturity from 1 Oct 21 to 30 Sep 22 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	1.94%
Long-term | Fixed Rate Advances Maturity from 1 Oct 21 to 30 Sep 22 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	3.23%
Long-term | Fixed Rate Advances Maturity from 1 Oct 21 to 30 Sep 22 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.31%
Long-term | Fixed Rate Advances Maturity from 1 Oct 22 to 30 Sep 23
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2022
Date of maturity to	Sep. 30, 2023
Amount	$ 94,999	94,999
Long-term | Fixed Rate Advances Maturity from 1 Oct 22 to 30 Sep 23 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.00%
Long-term | Fixed Rate Advances Maturity from 1 Oct 22 to 30 Sep 23 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	3.22%
Long-term | Fixed Rate Advances Maturity from 1 Oct 22 to 30 Sep 23 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.52%
Long-term | Fixed Rate Advances Maturity from 1 Oct 23 to 30 Sep 24
Federal Home Loan Bank, Advances [Line Items]
Date of maturity from	Oct. 1, 2023
Date of maturity to	Sep. 30, 2024
Amount	$ 67,998	$ 67,998
Long-term | Fixed Rate Advances Maturity from 1 Oct 23 to 30 Sep 24 | Minimum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	2.38%
Long-term | Fixed Rate Advances Maturity from 1 Oct 23 to 30 Sep 24 | Maximum
Federal Home Loan Bank, Advances [Line Items]
Stated interest rate range	3.20%
Long-term | Fixed Rate Advances Maturity from 1 Oct 23 to 30 Sep 24 | Weighted average
Federal Home Loan Bank, Advances [Line Items]
Weighted average interest rate	2.88%

INTEREST RATE SWAPS (Details)

INTEREST RATE SWAPS (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2021	Sep. 30, 2020
Derivative [Line Items]
Unrealized Gain (Loss)	$ (14,881)	$ (20,960)
Interest rate swap contract maturing on 1 May 2028
Derivative [Line Items]
Hedge Item	State and political subdivisions	State and political subdivisions
Notional Amount	$ 21,570	$ 21,570
Receive Rate	3 Mth Libor	3 Mth Libor
Unrealized Gain (Loss)	$ (2,316)	$ (3,834)
Interest rate swap contract maturing on 1 Aug 2026
Derivative [Line Items]
Hedge Item	Commercial loans	Commercial loans
Notional Amount	$ 23,656	$ 23,656
Receive Rate	1 Mth Libor +225 to 276 bp	1 Mth Libor +225 to 276 bp
Unrealized Gain (Loss)	$ 0	$ 0
Interest rate swap contract maturing on 12 Jun 2026
Derivative [Line Items]
Hedge Item	30 day wholesale funding	30 day wholesale funding
Notional Amount	$ 90,000	$ 90,000
Receive Rate	1 Mth Libor	1 Mth Libor
Unrealized Gain (Loss)	$ (4,099)	$ (6,157)
Interest rate swap contract maturing on 27 Mar 24
Derivative [Line Items]
Hedge Item	90 day wholesale funding	90 day wholesale funding
Notional Amount	$ 135,000	$ 135,000
Receive Rate	3 Mth Libor	3 Mth Libor
Unrealized Gain (Loss)	$ (8,466)	$ (10,969)
Minimum | Interest rate swap contract maturing on 1 May 2028
Derivative [Line Items]
Pay rate	3.06%	3.06%
Maturity date	Feb. 1, 2027	Feb. 1, 2027
Minimum | Interest rate swap contract maturing on 1 Aug 2026
Derivative [Line Items]
Pay rate	4.10%	4.10%
Maturity date	Jun. 13, 2025	Jun. 13, 2025
Minimum | Interest rate swap contract maturing on 12 Jun 2026
Derivative [Line Items]
Pay rate	1.36%	1.36%
Maturity date	Feb. 15, 2024	Feb. 15, 2024
Minimum | Interest rate swap contract maturing on 27 Mar 24
Derivative [Line Items]
Pay rate	2.51%	2.51%
Maturity date	Jan. 11, 2024	Jan. 11, 2024
Maximum | Interest rate swap contract maturing on 1 May 2028
Derivative [Line Items]
Pay rate	3.07%	3.07%
Maturity date	May 1, 2028	May 1, 2028
Maximum | Interest rate swap contract maturing on 1 Aug 2026
Derivative [Line Items]
Pay rate	5.74%	5.74%
Maturity date	Aug. 1, 2026	Aug. 1, 2026
Maximum | Interest rate swap contract maturing on 12 Jun 2026
Derivative [Line Items]
Pay rate	2.70%	2.70%
Maturity date	Jun. 12, 2026	Jun. 12, 2026
Maximum | Interest rate swap contract maturing on 27 Mar 24
Derivative [Line Items]
Pay rate	2.78%	2.78%
Maturity date	Mar. 27, 2024	Mar. 27, 2024

INTEREST RATE SWAPS - Additiona

INTEREST RATE SWAPS - Additional Information (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2021USD ($)contractloan	Mar. 31, 2020USD ($)	Mar. 31, 2021USD ($)contractloan	Mar. 31, 2020USD ($)	Sep. 30, 2020contractloan
Derivative Instruments, Gain (Loss) [Line Items]
Number of hedges	13		13		13
Income (expense) from components excluded from assessment of cash flow hedge effectiveness, net | $	$ 3,000	$ (4,000)	$ (5,000)	$ (3,000)
Deposits as collateral for hedges | $	$ 26,300,000		$ 26,300,000
Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Number of hedges	9		9		9
Derivative Asset, Number of Instruments Held	7		7		7
Derivative Liability, Number of Instruments Held | loan	3		3		3

INCOME TAXES - Items that gave

INCOME TAXES - Items that gave rise to significant portions of deferred income taxes (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Deferred tax assets:
Allowance for loan losses	$ 2,074	$ 2,071
Nonaccrual interest	625	561
Accrued vacation	16	16
Capital loss carryforward	4	4
Split dollar life insurance	9	9
Post-retirement benefits	70	72
Realized loss on equity securities		3
Unrealized losses on interest rate swaps	2,637	3,596
Deferred compensation	756	781
Goodwill	52	58
Lease liability	276	0
Other	104	48
Employee benefit plans	214	187
Total deferred tax assets	6,837	7,406
Valuation allowance	4	4
Total deferred tax assets, net of valuation allowance	6,833	7,402
Deferred tax liabilities:
Property	173	137
Right of Use	251	0
Realized gain on equity securities	9	0
Unrealized gains on available for sale securities	2,227	2,813
Purchase accounting adjustments	359	321
Deferred loan fees	401	229
Total deferred tax liabilities	3,420	3,500
Net deferred tax assets	$ 3,413	$ 3,902

INCOME TAXES - Additional Infor

INCOME TAXES - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2021	Sep. 30, 2020
INCOME TAXES
Period of capital gains recognized	5 years
Valuation allowance	$ 4	$ 4

STOCK COMPENSATION PLANS - Summ

STOCK COMPENSATION PLANS - Summary of non-vested stock award activity (Details)	6 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Shares
Non-vested stock awards at beginning of period | shares	23,056
Granted | shares	0
Forfeited | shares	0
Vested | shares	(8,128)
Non-vested stock awards at the end of the period | shares	14,928
Weighted Average Grant Date Fair Value
Nonvested stock awards at beginning of period | $ / shares	$ 17.78
Granted | $ / shares	0
Forfeited | $ / shares	0
Vested | $ / shares	18.03
Non-vested stock awards at the end of the period | $ / shares	$ 17.66

STOCK COMPENSATION PLANS - Su_2

STOCK COMPENSATION PLANS - Summary of status of stock options under Stock Option Plan (Details) - 2008 Option Plan and 2014 SIP - Stock Options	6 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Shares
Options outstanding at beginning of period | shares	571,258
Exercised | shares	(15,000)
Forfeited | shares	(39,500)
Outstanding at the end of the period | shares	516,758
Exercisable at December 31 | shares	400,231
Weighted Average Exercise Price
Options outstanding at beginning of period | $ / shares	$ 14.58
Exercised | $ / shares	12.23
Forfeited | $ / shares	18.42
Outstanding at the end of the period | $ / shares	14.36
Exercisable at December 31 | $ / shares	$ 13.70

STOCK COMPENSATION PLANS - 2008

STOCK COMPENSATION PLANS - 2008 Recognition and Retention Plan (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		6 Months Ended
	Mar. 31, 2018	Aug. 31, 2016	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			0
2008 Recognition and Retention Plan ("2008 RRP")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased by RRP trust			213,528
Value of shares purchased in open market by RRP trust			$ 2.5
Average price per share of common stock purchased in the open market			$ 11.49
Percentage of vesting per year			20.00%
Vesting period of awards granted			5 years
Number of shares granted	8,209	7,473

STOCK COMPENSATION PLANS - Opti

STOCK COMPENSATION PLANS - Option Plan (Details) - USD ($)	1 Months Ended							3 Months Ended		6 Months Ended
	Sep. 30, 2020	Jul. 31, 2019	Mar. 31, 2018	May 30, 2017	Mar. 31, 2017	Aug. 31, 2016	Feb. 28, 2015	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted										0
2008 Stock Option Plan (the "2008 Option Plan")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			18,235	283
2008 Stock Option Plan (the "2008 Option Plan") | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vesting and exercisable per year										20.00%
Vesting period of options										5 years
Exercisable period of options after grant date										10 years
Number of common stock available for issuance								533,808		533,808
Number of shares purchased for award						18,866
2014 Stock Incentive Plan (the "2014 SIP")
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted				25,000	17,128	3,027
2014 Stock Incentive Plan (the "2014 SIP") | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares for issuance pursuant to options								714,145		714,145
Number of shares granted	12,500				22,828	8,634
2014 Stock Incentive Plan (the "2014 SIP") | Restricted stock awards or units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock available for issuance							285,655
Number of shares granted							233,500
2008 RRP and 2014 SIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares purchased for award							605,000
Number of shares granted			18,291
2008 RRP and 2014 SIP | Restricted stock awards or units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options										5 years
Recognized compensation expense								$ 41,000	$ 120,000
Additional compensation expense for shares awarded remained unrecognized								339,000		$ 339,000
2008 Option Plan and 2014 SIP | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		39,702	159,265
Recognized compensation expense								41,000	$ 117,000	84,000	$ 270,000
Additional compensation expense for shares awarded remained unrecognized								$ 239,000		239,000
2008 Option Plan and 2014 SIP | Restricted stock awards or units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized compensation expense										$ 84,000	$ 256,000

STOCK COMPENSATION PLANS - Op_2

STOCK COMPENSATION PLANS - Option Granted (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining contractual term for options outstanding			5 years 1 month 6 days
Exercise price and fair value	$ 18.46		$ 18.46
2008 Option Plan and 2014 SIP | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized compensation expense	$ 41,000	$ 117,000	$ 84,000	$ 270,000
Additional compensation expense for shares awarded remained unrecognized	$ 239,000		$ 239,000
Weighted average period for recognition of nonvested awards			2 years 4 months 24 days
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			$ 2.98
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			2.92
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			3.34
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			4.67
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			4.58
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			2.13
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			$ 3.18
Fair value, valuation method			Black-Scholes pricing model
Expected term			7 years
Volatility rate			14.37%
Expected interest rate			2.22%
Expected yield			0.69%
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2017 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price and fair value	$ 17.43		$ 17.43
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			$ 3.63
2008 Option Plan and 2014 SIP | Stock Options | Granted In March 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value, valuation method			Black-Scholes pricing model
Expected term			7 years
Volatility rate			15.90%
Expected interest rate			2.82%
Expected yield			1.08%
2008 Option Plan and 2014 SIP | Stock Options | Granted in fiscal 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			$ 3.38
Fair value, valuation method			Black-Scholes pricing model
Exercise price and fair value	18.16		$ 18.16
Expected term			7 years
Volatility rate			17.76%
Expected interest rate			1.87%
Expected yield			1.10%
2008 Option Plan and 2014 SIP | Stock Options | Granted In Fiscal 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of options granted per share			$ 2.31
Fair value, valuation method			Black-Scholes pricing model
Exercise price and fair value	$ 10		$ 10
Expected term			7 years
Volatility rate			33.22%
Expected interest rate			0.41%
Expected yield			2.80%

COMMITMENTS AND CONTINGENT LI_2

COMMITMENTS AND CONTINGENT LIABILITIES (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2021	Sep. 30, 2020
COMMITMENTS AND CONTINGENT LIABILITIES
Outstanding commitments	$ 1,000
Aggregate undisbursed portion of loans-in-process	89,912	$ 86,862
Loan Origination Commitments
COMMITMENTS AND CONTINGENT LIABILITIES
Outstanding commitments	55,000	29,900
Aggregate undisbursed portion of loans-in-process	$ 89,900	$ 86,900
Loan Origination Commitments | Minimum
COMMITMENTS AND CONTINGENT LIABILITIES
Market interest rate on fixed and variable rate loans	3.13%	3.25%
Loan Origination Commitments | Maximum
COMMITMENTS AND CONTINGENT LIABILITIES
Market interest rate on fixed and variable rate loans	4.50%	4.75%
Unused lines of Credit
COMMITMENTS AND CONTINGENT LIABILITIES
Outstanding commitments	$ 45,900	$ 40,100
Letters of Credit
COMMITMENTS AND CONTINGENT LIABILITIES
Outstanding commitments	$ 1,100	$ 1,100

FAIR VALUE MEASUREMENT - Assets

FAIR VALUE MEASUREMENT - Assets measured at fair value on recurring basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Assets:
Assets, Total	$ 353,861	$ 420,415
Liabilities:
Liabilities, Total	14,881	20,960
Level 1
Assets:
Assets, Total	54	51
Level 2
Assets:
Assets, Total	353,807	420,364
Liabilities:
Liabilities, Total	14,881	20,960
U.S. Government and agency obligations
Assets:
Assets, Total	10,893	22,394
U.S. Government and agency obligations | Level 2
Assets:
Assets, Total	10,893	22,394
State and political subdivisions
Assets:
Assets, Total	79,351	79,621
State and political subdivisions | Level 2
Assets:
Assets, Total	79,351	79,621
Mortgage-Backed Securities
Assets:
Assets, Total	179,701	236,566
Mortgage-Backed Securities | Level 2
Assets:
Assets, Total	179,701	236,566
Corporate bonds
Assets:
Assets, Total	83,862	81,783
Corporate bonds | Level 2
Assets:
Assets, Total	83,862	81,783
Equity security - FHLMC preferred stock
Assets:
Assets, Total	54	51
Equity security - FHLMC preferred stock | Level 1
Assets:
Assets, Total	54	51
Interest rate swap
Liabilities:
Liabilities, Total	14,881	20,960
Interest rate swap | Level 2
Liabilities:
Liabilities, Total	$ 14,881	$ 20,960

FAIR VALUE MEASUREMENT - Asse_2

FAIR VALUE MEASUREMENT - Assets measured at fair value on a non-recurring basis and the adjustments to the carrying value (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Assets:
Loans receivable, net	$ 620,875	$ 588,300
Liabilities:
Advances from FHLB long-term	251,639	260,253
Carrying Amount
Assets:
Investment and mortgage-backed securities held to maturity	22,270	22,860
Loans receivable, net	620,875	588,300
Liabilities:
Certificates of deposit	301,922	269,610
Advances from FHLB long-term	251,639	260,253
Fair Value
Assets:
Investment and mortgage-backed securities held to maturity	23,460	24,330
Loans receivable, net	622,637	593,768
Liabilities:
Certificates of deposit	311,058	278,224
Advances from FHLB long-term	261,171	274,172
Level 1
Assets:
Investment and mortgage-backed securities held to maturity	0	0
Loans receivable, net	0
Liabilities:
Certificates of deposit	311,058	278,224
Advances from FHLB long-term	261,171	274,172
Level 2
Assets:
Investment and mortgage-backed securities held to maturity	23,460	24,330
Loans receivable, net	0
Liabilities:
Certificates of deposit	0	0
Advances from FHLB long-term	0	0
Level 3
Assets:
Investment and mortgage-backed securities held to maturity	0	0
Loans receivable, net	622,637	593,768
Liabilities:
Certificates of deposit	0	0
Advances from FHLB long-term	$ 0	$ 0

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS - Related to acquisition of Polonia Bancorp (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Goodwill
Balance, Goodwill			$ 6,102
Balance, Goodwill	$ 6,102		6,102
Core deposit intangible
Balance			340
Balance	291		291
GOODWILL AND OTHER INTANGIBLE ASSETS, Total
Amortization	(23)	$ (26)	(49)	$ (56)
Polonia Bancorp
Goodwill
Balance, Goodwill			6,102
Additions/Adjustments			0
Balance, Goodwill	6,102		6,102
GOODWILL AND OTHER INTANGIBLE ASSETS, Total
Balance, Total			6,442
Additions/Adjustments			0
Amortization			(49)
Balance, Total	6,393		6,393
Polonia Bancorp | Core deposit intangible
Core deposit intangible
Balance			340
Additions/Adjustments			0
Amortization			(49)
Balance	$ 291		$ 291
Amortization Period			10 years

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS - Future fiscal periods amortization expense (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
GOODWILL AND OTHER INTANGIBLE ASSETS
2021	$ 44
2022	78
2023	64
2024	49
2025	34
Thereafter	22
Total	$ 291	$ 340

LEASES (Details)

LEASES (Details)	Mar. 31, 2021
Lessee, Lease, Description [Line Items]
Weighted-average remaining lease term - operating leases in years	6 years 10 months 6 days
Weighted-average discount rate - operating leases	2.00%
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term (in years)	5 years
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term (in years)	9 years

LEASES - Aggregate lease maturi

LEASES - Aggregate lease maturities and obligations (Details) $ in Thousands	Mar. 31, 2021USD ($)
Aggregate lease maturities and obligations
2021	$ 105
2022	213
2023	216
2024	220
2025	231
2025 and thereafter	423
Total lease payments	1,408
Less: interest	96
Present value of lease liabilities	$ 1,312

LEASES - Narrative (Details)

LEASES - Narrative (Details)	3 Months Ended	6 Months Ended
	Mar. 31, 2021USD ($)	Mar. 31, 2021USD ($)
Operating lease ROU assets	$ 1,200,000	$ 1,200,000
Operating lease liabilities	1,312,000	1,312,000
Operating lease liabilities	1,408,000	1,408,000
Operating lease cost	$ 51,000	$ 102,000
Minimum
Remaining lease term (in years)	5 years	5 years
Maximum
Remaining lease term (in years)	9 years	9 years