SEGMENT INFORMATION - Schedule of Segment Information and Statement of Financial Condition (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 1,573,100	$ 1,154,818	$ 990,918	$ 1,092,900
Goodwill	885,224	885,898
Other segment assets	18,382,091	18,773,587
Total assets	20,840,415	20,814,303
WSFS Bank
Segment Reporting Information [Line Items]
Cash and cash equivalents	1,170,666	686,735
Goodwill	753,586	753,586
Other segment assets	17,882,223	18,292,205
Total assets	19,806,475	19,732,526
Cash Connect
Segment Reporting Information [Line Items]
Cash and cash equivalents	361,274	424,907
Goodwill	0	0
Other segment assets	8,313	12,536
Total assets	369,587	437,443
Wealth and Trust
Segment Reporting Information [Line Items]
Cash and cash equivalents	41,160	43,176
Goodwill	131,638	132,312
Other segment assets	491,555	468,846
Total assets	$ 664,353	$ 644,334