Business and Basis of Presentation (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) subsidiary Office	Dec. 31, 2018 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	118
Number of unconsolidated subsidiary | subsidiary	1
Number of majority-owned subsidiary | subsidiary	1
Cypress
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Assets under management | $	$ 1,200.0	$ 948.8
West Capital
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Assets under management | $	767.8	$ 695.5
WSFS Capital Trust III
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Amount of aggregate principal issued | $	67.0
Trust preferred securities redeemed | $	$ 51.5
WSFS Financial Corporation
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of wholly-owned subsidiaries | subsidiary	4
Delaware
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	45
Pennsylvania
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	55
New Jersey
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	16
Virginia
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	1
Nevada
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of office locations	1