Segment Information - Details of Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Interest income	$ 35,882	$ 37,763	$ 71,473	$ 76,986
Noninterest income	19,539	28,992	37,613	45,750
Total revenue	55,421	66,755	109,086	122,736
Interest expense	3,826	5,685	7,837	12,378
Noninterest expenses	33,152	33,017	65,522	64,006
Provision for loan loss	1,680	16,383	3,911	24,628
Total expenses	38,658	55,085	77,270	101,012
Income before taxes	16,763	11,670	31,816	21,724
Provision for income taxes	5,855	4,340	11,168	7,950
Consolidated Net income	10,908	7,330	20,648	13,774
Capital expenditures	549	2,211	1,505		4,144
Cash and cash equivalents	537,522	467,251	537,522	467,251	500,887	468,017
Other segment assets	3,871,201		3,871,201		3,874,261
Total assets	4,408,723		4,408,723		4,375,148
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	59,655	71,708	117,530	132,546
Total expenses	42,892	60,038	85,714	110,822
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	2,282	2,527	4,616	5,142
Noninterest income	1,952	2,426	3,828	4,668
Total revenue	4,234	4,953	8,444	9,810
Interest expense	2,282	2,527	4,616	5,142
Noninterest expenses	1,952	2,426	3,828	4,668
Total expenses	4,234	4,953	8,444	9,810
WSFS Bank [Member]
Segment Reporting Information [Line Items]
Interest income	33,961	35,688	67,561	72,724
Noninterest income	9,333	20,969	18,560	30,498
Total revenue	43,294	56,657	86,121	103,222
Interest expense	3,693	5,478	7,533	11,953
Noninterest expenses	26,731	27,583	53,161	53,967
Provision for loan loss	1,535	15,494	3,781	23,790
Total expenses	31,959	48,555	64,475	89,710
Income before taxes	12,331	9,601	23,538	16,508
Capital expenditures	272	2,208	1,045		4,114
WSFS Bank [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	45,909	59,883	91,289	109,625
Total expenses	33,578	50,282	67,751	93,117
Cash and cash equivalents	59,041		59,041		68,419
Other segment assets	3,682,809		3,682,809		3,683,073
Total assets	3,741,850		3,741,850		3,751,492
WSFS Bank [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	914	1,048	1,817	2,156
Noninterest income	1,701	2,178	3,351	4,247
Total revenue	2,615	3,226	5,168	6,403
Interest expense	1,368	1,479	2,799	2,986
Noninterest expenses	251	248	477	421
Total expenses	1,619	1,727	3,276	3,407
Cash Connect [Member]
Segment Reporting Information [Line Items]
Noninterest income	6,025	4,473	11,052	8,546
Total revenue	6,025	4,473	11,052	8,546
Noninterest expenses	3,167	2,543	6,159	4,515
Total expenses	3,167	2,543	6,159	4,515
Income before taxes	2,138	1,241	3,452	2,656
Capital expenditures	277		460		10
Cash Connect [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	6,248	4,721	11,475	8,967
Total expenses	4,110	3,480	8,023	6,311
Cash and cash equivalents	475,745		475,745		430,382
Other segment assets	2,003		2,003		1,605
Total assets	477,748		477,748		431,987
Cash Connect [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Noninterest income	223	248	423	421
Total revenue	223	248	423	421
Interest expense	405	336	776	670
Noninterest expenses	538	601	1,088	1,126
Total expenses	943	937	1,864	1,796
Trust & Wealth Management [Member]
Segment Reporting Information [Line Items]
Interest income	1,921	2,075	3,912	4,262
Noninterest income	4,181	3,550	8,001	6,706
Total revenue	6,102	5,625	11,913	10,968
Interest expense	133	207	304	425
Noninterest expenses	3,254	2,891	6,202	5,524
Provision for loan loss	145	889	130	838
Total expenses	3,532	3,987	6,636	6,787
Income before taxes	2,294	828	4,826	2,560
Capital expenditures		3			20
Trust & Wealth Management [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	7,498	7,104	14,766	13,954
Total expenses	5,204	6,276	9,940	11,394
Cash and cash equivalents	2,736		2,736		2,086
Other segment assets	186,389		186,389		189,583
Total assets	189,125		189,125		191,669
Trust & Wealth Management [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	1,368	1,479	2,799	2,986
Noninterest income	28		54
Total revenue	1,396	1,479	2,853	2,986
Interest expense	509	712	1,041	1,486
Noninterest expenses	1,163	1,577	2,263	3,121
Total expenses	$ 1,672	$ 2,289	$ 3,304	$ 4,607