GOODWILL AND INTANGIBLE ASSETS - Schedule of Allocation of Goodwill to Our Reportable Operating Segments for Purposes of Goodwill Impairment Testing (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)
Goodwill [Roll Forward]
Goodwill beginning balance	$ 883,637
Goodwill from business combinations	2,261
Goodwill ending balance	885,898
WSFS Bank
Goodwill [Roll Forward]
Goodwill beginning balance	753,586
Goodwill from business combinations	0
Goodwill ending balance	753,586
Cash Connect
Goodwill [Roll Forward]
Goodwill beginning balance	0
Goodwill from business combinations	0
Goodwill ending balance	0
Wealth Management
Goodwill [Roll Forward]
Goodwill beginning balance	130,051
Goodwill from business combinations	2,261
Goodwill ending balance	$ 132,312