The value of the collateral (typically cash) that the entity receives in a financing transaction in exchange for securities lent. This item represents a liability in the financial statements of the lender of the securities.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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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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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Dividends received on equity and other investments during the current period.

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Borrowed Funds - Additional Information (Detail) - USD ($)			12 Months Ended
	Dec. 03, 2020	Jun. 13, 2016	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2005
Repurchase Agreement Counterparty [Line Items]
Securities sold under agreements to repurchase			$ 0	$ 0
Interest rates on advances from FHLB (as percent)			2.60%
Stock in Federal Home Loan Bank of Pittsburgh, at cost			$ 5,771,000	21,097,000
Collateralized borrowings			20,400,000	16,000,000.0
Federal Reserve Bank of Philadelphia
Repurchase Agreement Counterparty [Line Items]
Loans pledged as collateral			347,100,000	429,000,000.0
Borrowed funds			0	0
4.50% Senior Unsecured Notes Mature on 2026
Repurchase Agreement Counterparty [Line Items]
Interest rate on unsecured debt (as percent)		4.50%
Senior unsecured notes, percentage of principle amount to be redeemed (as percent)		100.00%
4.50% Senior Unsecured Notes Mature on 2026 \| LIBOR Rate
Repurchase Agreement Counterparty [Line Items]
Variable interest rate (as percent)		3.30%
WSFS Capital Trust III
Repurchase Agreement Counterparty [Line Items]
Aggregate principal amount of Pooled Floating Rate Securities					$ 67,000,000.0
WSFS Capital Trust III \| LIBOR Rate
Repurchase Agreement Counterparty [Line Items]
Variable interest rate (as percent)					1.77%
FHLB advances
Repurchase Agreement Counterparty [Line Items]
Stock in Federal Home Loan Bank of Pittsburgh, at cost			5,800,000	21,100,000
Dividends from the FHLB			$ 500,000	$ 1,500,000
Senior Notes
Repurchase Agreement Counterparty [Line Items]
Debt instrument, face amount		$ 100,000,000.0
Senior Notes 2020
Repurchase Agreement Counterparty [Line Items]
Debt instrument, face amount	$ 150,000,000.0
Interest rate on unsecured debt (as percent)	2.75%
Redemption price, percentage (as percent)	100.00%
Senior Notes 2020 \| LIBOR Rate
Repurchase Agreement Counterparty [Line Items]
Variable interest rate (as percent)	2.485%