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</LabelSeparator><Level>2</Level><ElementName>us-gaap_BasisOfAccounting</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="Context_3ME_31-Mar-2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font: /normal 'times new roman'; color: #000000; text-transform: none; text-indent: 0px; letter-spacing: normal; word-spacing: 0px; white-space: normal; -webkit-text-stroke-width: 0px;"&gt;&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;b&gt;&lt;font style="font-size: 10pt; font-weight: bold; ; font-family: times new roman;" size="2"&gt;Note 1 &amp;#8212; Basis of Presentation&lt;/font&gt;&lt;/b&gt;&lt;/p&gt;
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&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;The unaudited interim consolidated financial statements include the accounts of Waterstone Financial,&amp;#160;Inc. (the &amp;#8220;Company&amp;#8221;) and the Company&amp;#8217;s subsidiaries.&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles (&amp;#8220;GAAP&amp;#8221;) for interim financial information, Rule&amp;#160;10-01 of Regulation&amp;#160;S-X and the instructions to Form&amp;#160;10-Q. The financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments (consisting of normal recurring accruals) necessary to present fairly the financial position, results of operations, changes in shareholders&amp;#8217; equity, and cash flows of the Company for the periods presented.&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;The accompanying unaudited consolidated financial statements and related notes should be read in conjunction with the Company&amp;#8217;s December&amp;#160;31, 2012 Annual Report on Form&amp;#160;10-K. Operating results for the three months ended March&amp;#160;31, 2013 are not necessarily indicative of the results that may be expected for the year ending December&amp;#160;31, 2013 or for any other period.&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;The preparation of the unaudited consolidated financial statements requires management of the Company to make a number of estimates and assumptions relating to the reported amount of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the period.&amp;#160; Significant items subject to such estimates and assumptions include the allowance for loan losses, deferred income taxes and real estate owned.&amp;#160; Actual results could differ from those estimates.&lt;/font&gt;&lt;/p&gt;
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&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;i&gt;&lt;font style="font-size: 10pt; font-style: italic; ; font-family: times new roman;" size="2"&gt;Recent Accounting Pronouncements&lt;/font&gt;&lt;/i&gt;&lt;/p&gt;
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&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;In January&amp;#160;2013, the Financial Accounting Standards Board (&amp;#8220;FASB&amp;#8221;) issued ASU No.&amp;#160;2013-01,&amp;#160;&lt;i&gt;Balance Sheet (Topic 210): Disclosures about Offsetting Assets and Liabilities&lt;/i&gt;, which amended disclosures by requiring improved information about financial instruments and derivative instruments that are either offset on the balance sheet or subject to an enforceable master netting arrangement or similar agreement, irrespective of whether they are offset on the balance sheet. Reporting entities are required to provide both net and gross information for these assets and liabilities in order to enhance comparability between those entities that prepare their financial statements on the basis of international financial reporting standards (&amp;#8220;IFRS&amp;#8221;). Companies were required to apply the amendments for fiscal years beginning on or after January&amp;#160;1, 2013, and interim periods within those years.&amp;#160; The adoption of this accounting standard did not have a material impact on the Company&amp;#8217;s results of operation, financial position, or liquidity.&lt;/font&gt;&lt;/p&gt;&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/p&gt;
&lt;p style="margin: 0in 0in 0pt;"&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;In February&amp;#160;2013, the FASB issued ASU No.&amp;#160;2013-02,&amp;#160;&lt;i&gt;Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income&lt;/i&gt;.&amp;#160; Under this standard, an entity is required to provide information about the amounts reclassified out of accumulated OCI by component. In addition, an entity is required to present, either on the face of the financial statements or in the notes, significant amounts reclassified out of accumulated OCI by the respective line items of net income, but only if the amount reclassified is required to be reclassified in its entirety in the same reporting period. For amounts that are not required to be reclassified in their entirety to net income, an entity is required to cross-reference to &lt;/font&gt;&lt;font style="font-size: 10pt; ; font-family: times new roman;" size="2"&gt;other disclosures that provide additional details about those amounts. This standard does not change the current requirements for reporting net income or other comprehensive income in the financial statements and was effective for interim and annual periods beginning on or after December&amp;#160;15, 2012. The adoption of this accounting standard did not have a material impact on the Company&amp;#8217;s results of operation, financial position, or liquidity.&lt;/font&gt;&lt;/p&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Basis of Presentation</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Basis of Presentation</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://wsbonline.com/role/BasisOfPresentation</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
