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Amount of contractually required payments receivable at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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Includes amounts for loans individually evaluated for impairment and purchased credit impaired loans that have become impaired since acquisition date.

No definition available.

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Impaired Loans Average Loan Balances

No definition available.

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Impaired Loans Contractual Principal Balances

No definition available.

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Impaired Loans Related Specific Reserve

No definition available.

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Impaired Loans With No Specific Reserve

No definition available.

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Impaired Loans With Specific Reserve

No definition available.

Name:	wsfs_ImpairedLoansWithSpecificReserve
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Period Type:	instant

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Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=wsfs_CommercialMortgagesMember
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Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
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Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
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Data Type:	na
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Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
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