SEGMENT INFORMATION - Schedule of Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Interest income	$ 258,421	$ 273,384	$ 762,489	$ 800,243
Interest expense	74,398	95,880	223,755	273,012
Net interest income	184,023	177,504	538,734	527,231
Noninterest income	86,471	90,158	255,377	257,613
Provision for credit losses	6,566	18,422	36,537	53,374
Salaries, benefits and other compensation	91,661	86,124	263,283	245,179
Occupancy expense	8,498	9,595	27,220	28,461
Equipment expense	12,933	12,076	39,439	34,822
Professional fees	4,942	3,819	15,851	13,081
Noninterest expenses	163,056	163,723	474,194	468,563
Income before taxes	100,872	85,517	283,380	262,907
Income tax provision	24,405	21,108	68,825	63,567
Consolidated net income	76,467	64,409	214,555	199,340
Net income (loss) attributable to noncontrolling interest	18	(26)	(116)	(129)
Net income attributable to WSFS	76,449	64,435	214,671	199,469
Operating Segments
Segment Reporting Information [Line Items]
Total revenue	280,827	277,258	823,139	811,585
Total expenses	179,955	191,741	539,759	548,678
Income before taxes	100,872	85,517	283,380	262,907
Income tax provision	24,405	21,108	68,825	63,567
Consolidated net income	76,467	64,409	214,555	199,340
Net income (loss) attributable to noncontrolling interest	18	(26)	(116)	(129)
Net income attributable to WSFS	76,449	64,435	214,671	199,469
Capital expenditures for the period ended	1,232	3,638	5,639	10,595
Operating Segments | WSFS Bank
Segment Reporting Information [Line Items]
Total revenue	192,469	190,781	564,508	563,689
Total expenses	128,345	137,340	382,814	390,613
Income before taxes	64,124	53,441	181,694	173,076
Capital expenditures for the period ended	1,061	2,896	4,856	9,289
Operating Segments | Cash Connect
Segment Reporting Information [Line Items]
Total revenue	22,043	27,681	64,641	79,347
Total expenses	19,697	26,052	57,448	74,988
Income before taxes	2,346	1,629	7,193	4,359
Capital expenditures for the period ended	88	124	197	247
Operating Segments | Wealth and Trust
Segment Reporting Information [Line Items]
Total revenue	66,315	58,796	193,990	168,549
Total expenses	31,913	28,349	99,497	83,077
Income before taxes	34,402	30,447	94,493	85,472
Capital expenditures for the period ended	83	618	586	1,059
Operating Segments | External Customers
Segment Reporting Information [Line Items]
Interest income	258,421	273,384	762,489	800,243
Interest expense	74,398	95,880	223,755	273,012
Net interest income	184,023	177,504	538,734	527,231
Noninterest income	86,471	90,158	255,377	257,613
Total revenue	270,494	267,662	794,111	784,844
Provision for credit losses	6,566	18,422	36,537	53,374
Salaries, benefits and other compensation	91,661	86,124	263,283	245,179
Occupancy expense	8,498	9,595	27,220	28,461
Equipment expense	12,933	12,076	39,439	34,822
Professional fees	4,942	3,819	15,851	13,081
Other segment items	45,022	52,109	128,401	147,020
Total expenses	169,622	182,145	510,731	521,937
Operating Segments | External Customers | WSFS Bank
Segment Reporting Information [Line Items]
Interest income	251,766	267,430	743,534	782,950
Interest expense	66,248	86,768	200,323	241,528
Net interest income	185,518	180,662	543,211	541,422
Noninterest income	19,353	21,338	55,523	60,198
Total revenue	204,871	202,000	598,734	601,620
Provision for credit losses	6,563	18,426	31,246	53,046
Salaries, benefits and other compensation	72,799	69,029	206,872	194,945
Occupancy expense	8,324	9,281	26,350	27,635
Equipment expense	10,333	9,146	31,669	27,242
Professional fees	3,100	2,872	9,741	8,520
Other segment items	26,319	27,891	74,661	77,146
Total expenses	127,438	136,645	380,539	388,534
Operating Segments | External Customers | Cash Connect
Segment Reporting Information [Line Items]
Interest income	0	0	0	0
Interest expense	0	0	0	0
Net interest income	0	0	0	0
Noninterest income	25,275	31,805	74,111	89,155
Total revenue	25,275	31,805	74,111	89,155
Provision for credit losses	59	0	59	0
Salaries, benefits and other compensation	2,486	2,642	7,694	7,867
Occupancy expense	0	3	0	28
Equipment expense	0	0	0	0
Professional fees	0	0	0	0
Other segment items	15,418	21,836	44,931	62,463
Total expenses	17,963	24,481	52,684	70,358
Operating Segments | External Customers | Wealth and Trust
Segment Reporting Information [Line Items]
Interest income	6,655	5,954	18,955	17,293
Interest expense	8,150	9,112	23,432	31,484
Net interest income	(1,495)	(3,158)	(4,477)	(14,191)
Noninterest income	41,843	37,015	125,743	108,260
Total revenue	40,348	33,857	121,266	94,069
Provision for credit losses	(56)	(4)	5,232	328
Salaries, benefits and other compensation	16,376	14,453	48,717	42,367
Occupancy expense	174	286	870	798
Equipment expense	2,600	2,488	7,770	6,260
Professional fees	1,842	817	6,110	4,219
Other segment items	3,285	2,979	8,809	9,073
Total expenses	24,221	21,019	77,508	63,045
Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	38,248	37,294	108,367	108,857
Interest expense	38,248	37,294	108,367	108,857
Net interest income	0	0	0	0
Noninterest income	10,333	9,596	29,028	26,741
Total revenue	10,333	9,596	29,028	26,741
Total expenses	10,333	9,596	29,028	26,741
Noninterest expenses	10,333	9,596	29,028	26,741
Inter-Segment Eliminations | WSFS Bank
Segment Reporting Information [Line Items]
Interest income	8,210	8,587	23,694	23,132
Interest expense	30,038	28,707	84,673	85,725
Net interest income	(21,828)	(20,120)	(60,979)	(62,593)
Noninterest income	9,426	8,901	26,753	24,662
Total revenue	(12,402)	(11,219)	(34,226)	(37,931)
Total expenses	907	695	2,275	2,079
Noninterest expenses	907	695	2,275	2,079
Inter-Segment Eliminations | Cash Connect
Segment Reporting Information [Line Items]
Interest income	498	293	1,384	1,119
Interest expense	4,179	4,885	12,153	12,308
Net interest income	(3,681)	(4,592)	(10,769)	(11,189)
Noninterest income	449	468	1,299	1,381
Total revenue	(3,232)	(4,124)	(9,470)	(9,808)
Total expenses	1,734	1,571	4,764	4,630
Noninterest expenses	1,734	1,571	4,764	4,630
Inter-Segment Eliminations | Wealth and Trust
Segment Reporting Information [Line Items]
Interest income	29,540	28,414	83,289	84,606
Interest expense	4,031	3,702	11,541	10,824
Net interest income	25,509	24,712	71,748	73,782
Noninterest income	458	227	976	698
Total revenue	25,967	24,939	72,724	74,480
Total expenses	7,692	7,330	21,989	20,032
Noninterest expenses	$ 7,692	$ 7,330	$ 21,989	$ 20,032