XML 38 R36.htm IDEA: XBRL DOCUMENT v2.4.1.9

Allowance for Losses on Loans - Loans Evaluated for Impairment (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	$ 108,323us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 108,700us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 112,347us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 114,931us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 118,158us-gaap_FinancingReceivableAllowanceForCreditLosses	$ 116,741us-gaap_FinancingReceivableAllowanceForCreditLosses
Loans receivable, gross	9,014,755us-gaap_LoansAndLeasesReceivableGrossCarryingAmount		8,669,717us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Single-Family Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	54,762us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	55,495us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	62,763us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	63,348us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	67,692us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	64,184us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Loans receivable, gross	5,546,403us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		5,572,244us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Construction - Speculative [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	5,445us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember	5,451us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember	6,742us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember	6,773us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember	8,142us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember	8,407us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Loans receivable, gross	163,657us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		140,060us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Construction - Custom [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	968us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember	965us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember	1,695us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember	1,599us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember	1,474us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember	882us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Loans receivable, gross	370,693us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		385,824us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Land - Acquisition & Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	7,405us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember	6,671us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember	5,592us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember	6,027us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember	7,084us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember	9,165us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Loans receivable, gross	107,181us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		80,359us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Land - Consumer Lot Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	3,035us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember	3,113us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember	3,077us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember	2,974us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember	3,274us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember	3,552us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Loans receivable, gross	104,558us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		111,130us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Multi-Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	4,673us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember	4,500us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember	4,248us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember	4,187us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember	4,109us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember	3,816us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
Loans receivable, gross	1,012,915us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember		920,285us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	6,734us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember	5,872us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember	7,548us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember	5,924us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember	5,868us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember	5,595us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Loans receivable, gross	885,177us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember		752,957us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	21,146us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember	23,328us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember	16,527us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember	20,403us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember	16,505us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember	16,614us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember
Loans receivable, gross	466,207us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember		434,088us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember
HELOC [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	850us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember	892us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember	928us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember	975us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember	943us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember	1,002us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember
Loans receivable, gross	136,439us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember		134,455us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	3,305us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember	2,413us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember	3,227us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember	2,721us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember	3,067us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember	3,524us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Loans receivable, gross	221,525us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember		138,315us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Loans Collectively Evaluated for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	108,323us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember		112,287us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember
Loans receivable, gross	8,287,193us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember		8,316,874us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember
Ratio	1.30%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember		1.40%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember
Loans Collectively Evaluated for Impairment [Member] | Single-Family Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	54,762us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		62,067us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Loans receivable, gross	5,476,667us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		5,487,331us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Ratio	1.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		1.10%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Loans Collectively Evaluated for Impairment [Member] | Construction - Speculative [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	5,445us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		6,682us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Loans receivable, gross	97,987us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		130,901us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Ratio	5.60%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		5.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Loans Collectively Evaluated for Impairment [Member] | Construction - Custom [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	968us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		1,695us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Loans receivable, gross	201,777us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		385,464us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Ratio	0.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		0.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Loans Collectively Evaluated for Impairment [Member] | Land - Acquisition & Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	7,405us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		5,592us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Loans receivable, gross	87,541us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		73,999us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Ratio	8.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		7.60%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Loans Collectively Evaluated for Impairment [Member] | Land - Consumer Lot Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	3,035us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		3,077us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Loans receivable, gross	89,279us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		95,684us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Ratio	3.40%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		3.20%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Loans Collectively Evaluated for Impairment [Member] | Multi-Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	4,673us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember		4,248us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
Loans receivable, gross	936,010us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember		911,162us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
Ratio	0.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember		0.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
Loans Collectively Evaluated for Impairment [Member] | Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	6,734us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember		7,548us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Loans receivable, gross	617,633us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember		563,534us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Ratio	1.10%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember		1.40%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Loans Collectively Evaluated for Impairment [Member] | Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	21,146us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember		17,223us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember
Loans receivable, gross	442,459us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember		421,816us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember
Ratio	4.80%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember		4.60%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_CommercialAndIndustrialLoansMember
Loans Collectively Evaluated for Impairment [Member] | HELOC [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	850us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember		928us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember
Loans receivable, gross	119,235us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember		114,393us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember
Ratio	0.70%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember		0.90%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_HomeEquityLineOfCreditMember
Loans Collectively Evaluated for Impairment [Member] | Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	3,305us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember		3,227us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Loans receivable, gross	218,605us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember		132,590us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Ratio	1.50%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember		2.40%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansCollectivelyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Loans Individually Evaluated for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember		60us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember
Loans receivable, gross	96,398us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember		134,736us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember		0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember
Loans Individually Evaluated for Impairment [Member] | Single-Family Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Loans receivable, gross	55,886us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		72,869us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember		0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Loans Individually Evaluated for Impairment [Member] | Construction - Speculative [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		60us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Loans receivable, gross	7,405us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		9,159us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember		0.70%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionSpeculativeMember
Loans Individually Evaluated for Impairment [Member] | Construction - Custom [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Loans receivable, gross	0us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		360us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember		0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_ConstructionCustomMember
Loans Individually Evaluated for Impairment [Member] | Land - Acquisition & Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Loans receivable, gross	3,298us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		3,833us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember		0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandAcquisitionAndDevelopmentMember
Loans Individually Evaluated for Impairment [Member] | Land - Consumer Lot Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Loans receivable, gross	12,723us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		12,939us-gaap_LoansAndLeasesReceivableGrossCarryingAmount / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Ratio	0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember		0.00%wfsl_AllowanceAsPercentageOfOutstandingLoansAndLeases / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_LandConsumerLotLoansMember
Loans Individually Evaluated for Impairment [Member] | Multi-Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for probable losses	0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember		0us-gaap_FinancingReceivableAllowanceForCreditLosses / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = wfsl_LoansIndividuallyEvaluatedForImpairmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = wfsl_MultiFamilyHousingPortfolioSegmentMember
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