Deposits - Schedule of Deposits and Respective Weighted-Average Interest Rates by Major Classifications (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Deposits [Line Items]
Weighted Average Interest Rate, Noninterest-bearing demand accounts	0.00%	0.00%
Weighted Average Interest Rate, Interest bearing demand accounts	0.13%	0.09%
Weighted Average Interest Rate, Money market accounts	0.51%	0.23%
Weighted Average Interest Rate, Savings and club accounts	0.05%	0.05%
Weighted Average Interest Rate, Certificates of deposit	1.20%	1.11%
Weighted Average Interest Rate, Total	0.64%	0.65%
Noninterest-bearing demand accounts	$ 142,924	$ 98,514
Interest bearing demand accounts	167,259	110,268
Money market accounts	249,947	162,418
Savings and club accounts	142,021	129,227
Certificates of deposit	512,669	596,327
Total	$ 1,214,820	$ 1,096,754
Weighted Average Interest Rate, Certificates of deposit	1.20%	1.11%
Certificates of deposit	$ 512,669	$ 596,327
0.00 - 2.00% [Member]
Deposits [Line Items]
Weighted Average Interest Rate, Certificates of deposit	1.14%	0.98%
Certificates of deposit	$ 484,341	$ 541,503
Weighted Average Interest Rate, Certificates of deposit	1.14%	0.98%
Certificates of deposit	$ 484,341	$ 541,503
2.01 - 4.00% [Member]
Deposits [Line Items]
Weighted Average Interest Rate, Certificates of deposit	2.26%	2.36%
Certificates of deposit	$ 28,328	$ 54,824
Weighted Average Interest Rate, Certificates of deposit	2.26%	2.36%
Certificates of deposit	$ 28,328	$ 54,824

Deposits.

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

+ References

+ Details

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- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

+ References

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- Definition

Amount of interest-bearing domestic certificate of deposit liabilities.

+ References

+ Details

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- Definition

Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

+ References

+ Details

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- Definition

Amount of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

+ References

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- Definition

The weighted average interest rate for all domestic deposit liabilities.

+ References

No definition available.

+ Details

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- Definition

The weighted average interest rate for domestic certificates of deposit liabilities.

+ References

No definition available.

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- Definition

The weighted average interest rate for domestic demand deposit liabilities.

+ References

No definition available.

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- Definition

The weighted average interest rate for domestic money market demand account deposit liabilities.

+ References

No definition available.

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- Definition

The weighted average interest rate for domestic notice of withdrawal demand deposit liabilities.

+ References

No definition available.

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- Definition

The weighted average interest rate for domestic savings deposit liabilities.

+ References

No definition available.

+ Details

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