2.4.0.8065 - Disclosure - Employee Benefit Plans (Details)truefalsefalse1false USDfalsefalse$Context_FYE_31-Dec-2012http://www.sec.gov/CIK0001569994duration2012-01-01T00:00:002012-12-31T00:00:00EmployeeStandardhttp://wsbonline.com/20130331Employeewsbf0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$Context_FYE_31-Dec-2011http://www.sec.gov/CIK0001569994duration2011-01-01T00:00:002011-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$Context_FYE_31-Dec-2010http://www.sec.gov/CIK0001569994duration2010-01-01T00:00:002010-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3us-gaap_DefinedBenefitPlanDisclosureLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Defined Benefit Plan Disclosure [Line Items]2false 4wsbf_MinimumAgeCriteriaForParticipationInBenefitPlanwsbf_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse0018 yearsfalsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaMinimum age requirement for eligible for participating in employee benefit plan.No definition available.false0Minimum age criteria for participation in benefit plan3false 4us-gaap_DefinedBenefitPlanContributionsByEmployerus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse7000070000USD$falsetruefalse2truefalsefalse00USD$falsetruefalse3truefalsefalse00USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe increase in the fair value of plan assets from contributions made by the employer.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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