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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair Value Of Guarantee With Standby Letters Of Credit

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Reverse Mortgages

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Fair Value Disclosures - Book Value and Estimated Fair Value of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Financial assets:
Cash and cash equivalents	$ 505,638	$ 508,039	$ 439,725	$ 484,426
Fair Value	786,497us-gaap_AvailableForSaleSecurities	740,124us-gaap_AvailableForSaleSecurities
Investment securities held-to-maturity	122,887us-gaap_HeldToMaturitySecurities	126,168us-gaap_HeldToMaturitySecurities
Loans, held-for-sale	46,892us-gaap_LoansReceivableHeldForSaleNet	28,508us-gaap_LoansReceivableHeldForSaleNet
Loans, net	3,189,138	3,156,652
Reverse mortgage loans	27,035wsfs_ReverseMortgages	29,298wsfs_ReverseMortgages
Stock in FHLB of Pittsburgh	27,655us-gaap_FederalHomeLoanBankStock	23,278us-gaap_FederalHomeLoanBankStock
Accrued interest receivable	12,004us-gaap_InterestReceivable	11,782us-gaap_InterestReceivable
Other assets	54,265us-gaap_OtherAssets	54,561us-gaap_OtherAssets
Financial liabilities:
Deposits	3,522,278us-gaap_Deposits	3,649,235us-gaap_Deposits
Borrowed funds	14,937us-gaap_OtherBorrowings	11,645us-gaap_OtherBorrowings
Accrued interest payable	1,621	1,004
Significant Other Observable Inputs (Level 2) [Member]
Financial assets:
Loans, held-for-sale	46,892	28,508
Book Value [Member]
Financial assets:
Fair Value	786,497		740,124
Investment securities held-to-maturity	122,887		126,168
Loans, held-for-sale	46,892		28,508
Book Value [Member] \| Quoted Prices in Active Markets for Identical Asset (Level 1) [Member]
Financial assets:
Cash and cash equivalents	505,638		508,039
Book Value [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Financial assets:
Loans, net	3,189,138		3,156,652
Stock in FHLB of Pittsburgh	27,655		23,278
Accrued interest receivable	12,004		11,782
Financial liabilities:
Deposits	3,522,278		3,649,235
Borrowed funds	874,557		667,775
Accrued interest payable	1,621		1,004
Book Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Financial assets:
Reverse mortgage loans	27,035		29,298
Financial liabilities:
Standby letters of credit	160		151
Fair Value [Member]
Financial assets:
Fair Value	786,497		740,124
Investment securities held-to-maturity	122,772		126,171
Loans, held-for-sale	46,892		28,508
Fair Value [Member] \| Quoted Prices in Active Markets for Identical Asset (Level 1) [Member]
Financial assets:
Cash and cash equivalents	505,638		509,039
Fair Value [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Financial assets:
Loans, net	3,159,907		3,121,855
Stock in FHLB of Pittsburgh	27,655		23,278
Accrued interest receivable	12,004		11,782
Financial liabilities:
Deposits	3,345,564		3,461,218
Borrowed funds	877,815		672,850
Accrued interest payable	1,621		1,004
Fair Value [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Financial assets:
Reverse mortgage loans	27,035		29,298
Other assets	4,837		4,837
Financial liabilities:
Standby letters of credit	$ 160		$ 151