Parent Only Financial Information (Condensed Statements of Financial Condition) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Assets
Cash and cash equivalents	$ 3,147	$ 2,477	$ 1,841
Loans receivable, net of allowance for loan losses of $740 and $923, respectively	223,786	207,996
Other assets	2,029us-gaap_OtherAssets	2,067us-gaap_OtherAssets
Total assets	273,344us-gaap_Assets	258,255us-gaap_Assets
Liabilities and Stockholders' Equity [Abstract]
Other liabilities	2,452us-gaap_OtherLiabilities	2,098us-gaap_OtherLiabilities
Stockholders' equity	23,876us-gaap_StockholdersEquity	22,735us-gaap_StockholdersEquity	21,958us-gaap_StockholdersEquity
Total liabilities and stockholders' equity	273,344	258,255
Parent Company [Member]
Assets
Cash and cash equivalents	398	844	337
Investment in Bank	21,775	20,318
ESOP loan receivable	1,487	1,509
Other assets	295	154
Total assets	23,955	22,825
Liabilities and Stockholders' Equity [Abstract]
Other liabilities	79	90
Stockholders' equity	23,876	22,735
Total liabilities and stockholders' equity	$ 23,955	$ 22,825

ESOP loan receivable

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Parent company's investment in CMS Bancorp.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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