SEGMENT INFORMATION - Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Interest income	$ 121,281	$ 133,855
Noninterest income	47,822	40,847
Total revenue	169,103	174,702
Interest expense	7,096	17,705
Noninterest expenses	95,619	88,496
(Recovery of) provision for credit losses	(20,160)	56,646
Total expenses	82,555	162,847
Income before taxes	86,548	11,855
Income tax provision	21,407	1,288
Net income	65,141	10,567
Less: Net income (loss) attributable to noncontrolling interest	59	(360)
Net income attributable to WSFS	65,082	10,927
Capital expenditures for the period ended	1,270	2,531
Operating Segments
Segment Reporting Information [Line Items]
Interest income	121,281	133,855
Noninterest income	47,822	40,847
Total revenue	177,293	182,803
Interest expense	7,096	17,705
Noninterest expenses	95,619	88,496
Total expenses	90,745	170,948
Income before taxes	86,548	11,855
Capital expenditures for the period ended	1,270	2,531
Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	3,808	4,792
Noninterest income	4,382	3,309
Total revenue	8,190	8,101
Interest expense	3,808	4,792
Noninterest expenses	4,382	3,309
Total expenses	8,190	8,101
WSFS Bank
Segment Reporting Information [Line Items]
Total revenue	142,479	149,381
(Recovery of) provision for credit losses	(19,593)	55,034
Total expenses	67,855	144,866
WSFS Bank | Operating Segments
Segment Reporting Information [Line Items]
Interest income	119,131	131,309
Noninterest income	23,348	18,072
Total revenue	147,018	154,231
Interest expense	6,904	16,747
Noninterest expenses	80,544	73,085
Total expenses	71,506	148,117
Income before taxes	75,512	6,114
Capital expenditures for the period ended	1,270	2,282
WSFS Bank | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	844	1,943
Noninterest income	3,695	2,907
Total revenue	4,539	4,850
Interest expense	2,964	2,849
Noninterest expenses	687	402
Total expenses	3,651	3,251
Cash Connect
Segment Reporting Information [Line Items]
Total revenue	9,702	11,679
(Recovery of) provision for credit losses	0	0
Total expenses	7,298	8,223
Cash Connect | Operating Segments
Segment Reporting Information [Line Items]
Interest income	0	0
Noninterest income	9,702	11,679
Total revenue	10,257	11,908
Interest expense	0	0
Noninterest expenses	7,298	8,223
Total expenses	8,565	9,918
Income before taxes	1,692	1,990
Capital expenditures for the period ended	0	211
Cash Connect | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	269	0
Noninterest income	286	229
Total revenue	555	229
Interest expense	180	954
Noninterest expenses	1,087	741
Total expenses	1,267	1,695
Wealth Management
Segment Reporting Information [Line Items]
Total revenue	16,922	13,642
(Recovery of) provision for credit losses	(567)	1,612
Total expenses	7,402	9,758
Wealth Management | Operating Segments
Segment Reporting Information [Line Items]
Interest income	2,150	2,546
Noninterest income	14,772	11,096
Total revenue	20,018	16,664
Interest expense	192	958
Noninterest expenses	7,777	7,188
Total expenses	10,674	12,913
Income before taxes	9,344	3,751
Capital expenditures for the period ended	0	38
Wealth Management | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	2,695	2,849
Noninterest income	401	173
Total revenue	3,096	3,022
Interest expense	664	989
Noninterest expenses	2,608	2,166
Total expenses	$ 3,272	$ 3,155