Fair Value of Financial Instruments - Schedule of Fair Values of the Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Financial assets:
Investment securities available for sale, at fair value	$ 390,410	$ 379,407
Fair value consists of the loan receivable	22,600	28,700
Mortgage servicing rights	398	412
Derivatives	453
Bank-owned life insurance	36,593	30,655
Financial liabilities:
Other borrowings	230,601	229,101
Advances by borrowers for taxes and insurance	4,956	4,273
Fair Value, Inputs, Level 1
Financial assets:
Investment securities available for sale, at fair value	25	25
Level II [Member]
Financial assets:
Investment securities available for sale, at fair value	382,900	375,171
Derivatives	453
Fair Value, Inputs, Level 3
Financial assets:
Investment securities available for sale, at fair value	7,485	4,211
Mortgage servicing rights	398	412
Carrying Value [Member]
Financial assets:
Cash and cash equivalents	43,658	18,758
Certificates of deposit	1,250	1,750
Investment securities available for sale, at fair value	390,410	379,407
Fair value consists of the loan receivable	1,219,213	1,102,118
Accrued interest receivable	5,769	5,068
Regulatory stock	15,463	13,831
Mortgage servicing rights	398	412
Derivatives	453
Bank-owned life insurance	36,593	30,655
Financial liabilities:
Deposits	1,214,820	1,096,754
Short-term borrowings	129,460	91,339
Other borrowings	230,601	229,101
Advances by borrowers for taxes and insurance	4,956	4,273
Accrued interest payable	1,046	866
Estimated Fair Value [Member]
Financial assets:
Cash and cash equivalents	43,658	18,758
Certificates of deposit	1,269	1,774
Investment securities available for sale, at fair value	390,410	379,407
Fair value consists of the loan receivable	1,237,759	1,123,436
Accrued interest receivable	5,769	5,068
Regulatory stock	15,463	13,831
Mortgage servicing rights	398	412
Derivatives	453
Bank-owned life insurance	36,593	30,655
Financial liabilities:
Deposits	1,218,894	1,100,677
Short-term borrowings	129,460	91,339
Other borrowings	231,911	230,255
Advances by borrowers for taxes and insurance	4,956	4,273
Accrued interest payable	1,046	866
Estimated Fair Value [Member] \| Fair Value, Inputs, Level 1
Financial assets:
Cash and cash equivalents	43,658	18,758
Investment securities available for sale, at fair value	25	25
Accrued interest receivable	5,769	5,068
Regulatory stock	15,463	13,831
Bank-owned life insurance	36,593	30,655
Financial liabilities:
Deposits	702,151	500,427
Short-term borrowings	129,460	91,339
Advances by borrowers for taxes and insurance	4,956	4,273
Accrued interest payable	1,046	866
Estimated Fair Value [Member] \| Level II [Member]
Financial assets:
Investment securities available for sale, at fair value	382,900	375,171
Derivatives	453
Estimated Fair Value [Member] \| Fair Value, Inputs, Level 3
Financial assets:
Certificates of deposit	1,269	1,774
Investment securities available for sale, at fair value	7,485	4,211
Fair value consists of the loan receivable	1,237,759	1,123,436
Mortgage servicing rights	398	412
Financial liabilities:
Deposits	516,743	600,250
Other borrowings	$ 231,911	$ 230,255

Accrued interest payable fair value disclosure.

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Accrued interest receivable fair value disclosure.

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Certificates of deposit at fair value.

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Regulatory Stock Fair Value Disclosure

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Carrying amount of accumulated prepayments received by financial institutions from borrowers for taxes (for example, property taxes) and insurance (for example, property and catastrophe) which will periodically be remitted to the appropriate governmental agency or vendor on behalf of the borrower.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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