SEGMENT INFORMATION - Schedule of Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Interest income	$ 251,139	$ 186,565	$ 719,291	$ 490,722
Noninterest income	72,668	62,651	202,666	195,254
Interest expense	68,537	9,734	172,315	21,718
Noninterest expenses	139,689	132,917	413,987	441,423
Provision for (recovery of) credit losses	18,414	7,454	63,255	34,693
Income before taxes	97,167	99,111	272,400	188,142
Income tax provision	22,904	25,767	66,880	49,929
Consolidated net income	74,263	73,344	205,520	138,213
Net income (loss) attributable to noncontrolling interest	97	(38)	272	287
Net income attributable to WSFS	74,166	73,382	205,248	137,926
Capital expenditures for the period ended			2,953	7,665
Operating Segments
Segment Reporting Information [Line Items]
Revenues, Total	366,444	275,419	1,039,127	744,601
Total expenses	269,277	176,308	766,727	556,459
Income before taxes	97,167	99,111	272,400	188,142
Income tax provision	22,904	25,767	66,880	49,929
Consolidated net income	74,263	73,344	205,520	138,213
Net income (loss) attributable to noncontrolling interest	97	(38)	272	287
Net income attributable to WSFS	74,166	73,382	205,248	137,926
Capital expenditures for the period ended	1,141	3,229	2,953	7,665
Operating Segments | External Customers
Segment Reporting Information [Line Items]
Interest income	251,139	186,565	719,291	490,722
Noninterest income	72,668	62,651	202,666	195,254
Revenues, Total	323,807	249,216	921,957	685,976
Interest expense	68,537	9,734	172,315	21,718
Noninterest expenses	139,689	132,917	413,987	441,423
Provision for (recovery of) credit losses	18,414	7,454	63,255	34,693
Total expenses	226,640	150,105	649,557	497,834
Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	34,564	18,644	93,781	36,733
Noninterest income	8,073	7,559	23,389	21,892
Revenues, Total	42,637	26,203	117,170	58,625
Interest expense	34,564	18,644	93,781	36,733
Noninterest expenses	8,073	7,559	23,389	21,892
Total expenses	42,637	26,203	117,170	58,625
WSFS Bank | Operating Segments
Segment Reporting Information [Line Items]
Revenues, Total	278,488	212,168	791,402	573,339
Total expenses	212,372	135,930	605,510	447,873
Income before taxes	66,116	76,238	185,892	125,466
Capital expenditures for the period ended	1,131	3,213	2,943	7,649
WSFS Bank | Operating Segments | External Customers
Segment Reporting Information [Line Items]
Interest income	245,520	183,107	703,210	481,683
Noninterest income	18,371	17,585	46,610	63,833
Revenues, Total	263,891	200,692	749,820	545,516
Interest expense	60,133	8,923	152,582	20,475
Noninterest expenses	105,655	104,817	314,751	361,949
Provision for (recovery of) credit losses	18,544	7,463	62,589	34,647
Total expenses	184,332	121,203	529,922	417,071
WSFS Bank | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	7,213	4,570	20,037	7,720
Noninterest income	7,384	6,906	21,545	20,103
Revenues, Total	14,597	11,476	41,582	27,823
Interest expense	27,351	14,074	73,744	29,013
Noninterest expenses	689	653	1,844	1,789
Total expenses	28,040	14,727	75,588	30,802
Cash Connect | Operating Segments
Segment Reporting Information [Line Items]
Revenues, Total	22,070	16,263	61,915	39,868
Total expenses	20,983	14,245	59,261	33,715
Income before taxes	1,087	2,018	2,654	6,153
Capital expenditures for the period ended	0	16	0	16
Cash Connect | Operating Segments | External Customers
Segment Reporting Information [Line Items]
Interest income	0	0	0	0
Noninterest income	21,231	15,416	59,402	37,500
Revenues, Total	21,231	15,416	59,402	37,500
Interest expense	0	0	0	0
Noninterest expenses	15,524	9,646	43,562	25,383
Provision for (recovery of) credit losses	0	0	0	0
Total expenses	15,524	9,646	43,562	25,383
Cash Connect | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	340	416	1,058	1,148
Noninterest income	499	431	1,455	1,220
Revenues, Total	839	847	2,513	2,368
Interest expense	4,068	3,414	11,478	4,896
Noninterest expenses	1,391	1,185	4,221	3,436
Total expenses	5,459	4,599	15,699	8,332
Wealth Management | Operating Segments
Segment Reporting Information [Line Items]
Revenues, Total	65,886	46,988	185,810	131,394
Total expenses	35,922	26,133	101,956	74,871
Income before taxes	29,964	20,855	83,854	56,523
Capital expenditures for the period ended	10	0	10	0
Wealth Management | Operating Segments | External Customers
Segment Reporting Information [Line Items]
Interest income	5,619	3,458	16,081	9,039
Noninterest income	33,066	29,650	96,654	93,921
Revenues, Total	38,685	33,108	112,735	102,960
Interest expense	8,404	811	19,733	1,243
Noninterest expenses	18,510	18,454	55,674	54,091
Provision for (recovery of) credit losses	(130)	(9)	666	46
Total expenses	26,784	19,256	76,073	55,380
Wealth Management | Inter-Segment Eliminations
Segment Reporting Information [Line Items]
Interest income	27,011	13,658	72,686	27,865
Noninterest income	190	222	389	569
Revenues, Total	27,201	13,880	73,075	28,434
Interest expense	3,145	1,156	8,559	2,824
Noninterest expenses	5,993	5,721	17,324	16,667
Total expenses	$ 9,138	$ 6,877	$ 25,883	$ 19,491