SEGMENT INFORMATION - Details of Segment Information - Statement of Financial Condition (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 2,064,161	$ 1,654,735
Goodwill	472,828	472,828
Other segment assets	12,193,463	12,206,351
Total assets	14,730,452	14,333,914
WSFS Bank
Segment Reporting Information [Line Items]
Cash and cash equivalents	1,627,674	1,246,394
Goodwill	452,629	452,629
Other segment assets	11,952,186	11,963,345
Total assets	14,032,489	13,662,368
Cash Connect
Segment Reporting Information [Line Items]
Cash and cash equivalents	423,406	397,878
Goodwill	0	0
Other segment assets	7,576	6,997
Total assets	430,982	404,875
Wealth Management
Segment Reporting Information [Line Items]
Cash and cash equivalents	13,081	10,463
Goodwill	20,199	20,199
Other segment assets	233,701	236,009
Total assets	$ 266,981	$ 266,671