SEGMENT INFORMATION - Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Interest income	$ 112,902	$ 125,883	$ 234,183	$ 259,738
Noninterest income	49,018	64,375	96,840	105,222
Total revenue	161,920	190,258	331,023	364,960
Interest expense	6,153	12,127	13,249	29,832
Noninterest expenses	96,032	93,435	191,651	181,931
(Recovery of) provision for credit losses	(67,563)	94,754	(87,723)	151,400
Total expenses	34,622	200,316	117,177	363,163
Income (loss) before taxes	127,298	(10,058)	213,846	1,797
Income tax provision (benefit)	31,687	(2,247)	53,094	(959)
Net income (loss)	95,611	(7,811)	160,752	2,756
Less: Net income (loss) attributable to noncontrolling interest	(56)	(700)	3	(1,060)
Net income (loss) attributable to WSFS	95,667	(7,111)	160,749	3,816
Capital expenditures for the period ended			3,005	2,830
Operating Segments
Segment Reporting Information [Line Items]
Interest income	112,902	125,883	234,183	259,738
Noninterest income	49,018	64,375	96,840	105,222
Total revenue	170,742	197,951	348,035	380,754
Interest expense	6,153	12,127	13,249	29,832
Noninterest expenses	96,032	93,435	191,651	181,931
Total expenses	43,444	208,009	134,189	378,957
Income (loss) before taxes	127,298	(10,058)	213,846	1,797
Capital expenditures for the period ended	1,735	299	3,005	2,830
Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	4,201	3,616	8,009	8,408
Noninterest income	4,621	4,077	9,003	7,386
Total revenue	8,822	7,693	17,012	15,794
Interest expense	4,201	3,616	8,009	8,408
Noninterest expenses	4,621	4,077	9,003	7,386
Total expenses	8,822	7,693	17,012	15,794
WSFS Bank
Segment Reporting Information [Line Items]
Total revenue	133,007	168,014	275,486	317,395
(Recovery of) provision for credit losses	(66,385)	93,819	(85,978)	148,853
Total expenses	20,078	185,267	87,933	330,133
WSFS Bank | Operating Segments
Segment Reporting Information [Line Items]
Interest income	110,725	123,710	229,856	255,019
Noninterest income	22,282	44,304	45,630	62,376
Total revenue	137,639	172,493	284,657	326,724
Interest expense	5,983	11,659	12,887	28,406
Noninterest expenses	80,480	79,789	161,024	152,874
Total expenses	24,268	188,481	95,774	336,598
Income (loss) before taxes	113,371	(15,988)	188,883	(9,874)
Capital expenditures for the period ended	1,735	155	3,005	2,437
WSFS Bank | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	842	937	1,686	2,880
Noninterest income	3,790	3,542	7,485	6,449
Total revenue	4,632	4,479	9,171	9,329
Interest expense	3,359	2,679	6,323	5,528
Noninterest expenses	831	535	1,518	937
Total expenses	4,190	3,214	7,841	6,465
Cash Connect
Segment Reporting Information [Line Items]
Total revenue	11,213	9,008	20,915	20,687
(Recovery of) provision for credit losses	0	0	0	0
Total expenses	7,288	6,413	14,586	14,636
Cash Connect | Operating Segments
Segment Reporting Information [Line Items]
Interest income	0	0	0	0
Noninterest income	11,213	9,008	20,915	20,687
Total revenue	11,857	9,433	22,114	21,341
Interest expense	0	0	0	0
Noninterest expenses	7,288	6,413	14,586	14,636
Total expenses	8,599	7,443	17,164	17,361
Income (loss) before taxes	3,258	1,990	4,950	3,980
Capital expenditures for the period ended	0	45	0	256
Cash Connect | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	328	237	597	237
Noninterest income	316	188	602	417
Total revenue	644	425	1,199	654
Interest expense	207	131	387	1,085
Noninterest expenses	1,104	899	2,191	1,640
Total expenses	1,311	1,030	2,578	2,725
Wealth Management
Segment Reporting Information [Line Items]
Total revenue	17,700	13,236	34,622	26,878
(Recovery of) provision for credit losses	(1,178)	935	(1,745)	2,547
Total expenses	7,256	8,636	14,658	18,394
Wealth Management | Operating Segments
Segment Reporting Information [Line Items]
Interest income	2,177	2,173	4,327	4,719
Noninterest income	15,523	11,063	30,295	22,159
Total revenue	21,246	16,025	41,264	32,689
Interest expense	170	468	362	1,426
Noninterest expenses	8,264	7,233	16,041	14,421
Total expenses	10,577	12,085	21,251	24,998
Income (loss) before taxes	10,669	3,940	20,013	7,691
Capital expenditures for the period ended	0	99	0	137
Wealth Management | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	3,031	2,442	5,726	5,291
Noninterest income	515	347	916	520
Total revenue	3,546	2,789	6,642	5,811
Interest expense	635	806	1,299	1,795
Noninterest expenses	2,686	2,643	5,294	4,809
Total expenses	$ 3,321	$ 3,449	$ 6,593	$ 6,604