Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Name:	us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Loans and leases receivable acquired non impaired loans.

No definition available.

Name:	wsfs_LoansAndLeasesReceivableAcquiredNonImpairedLoans
Namespace Prefix:	wsfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Modifications Recorded Investment Financing Receivable Individually Evaluated for Impairment

No definition available.

Name:	wsfs_ModificationsRecordedInvestmentFinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix:	wsfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage Of Loans And Leases Receivable Gross Carrying Amount

No definition available.

Name:	wsfs_PercentageOfLoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix:	wsfs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Reverse Mortgage, Fair Value

No definition available.

Name:	wsfs_ReverseMortgageFairValue
Namespace Prefix:	wsfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ConsumerLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_NonperformingFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_PerformingFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_InternalCreditAssessmentAxis=wsfs_AcquiredImpairedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: