Segment Information - Details of Segment Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Interest income	$ 37,785,000	$ 35,591,000
Noninterest income	18,364,000	18,074,000
Total revenue	60,358,000	57,875,000
Interest expense	3,741,000	4,011,000
Noninterest expenses	34,178,000	32,370,000
Provision for loan loss	2,630,000	2,231,000
Total expenses	44,758,000	42,822,000
Income before taxes	15,600,000	15,053,000
Provision for income taxes	(1,311,000)	5,313,000
Consolidated net income	16,911,000	9,740,000
Capital expenditures	537,000	956,000
Cash and cash equivalents	439,725,000	530,612,000	484,426,000	500,887,000
Other segment assets	4,106,237,000		4,031,337,000
Total assets	4,545,962,000		4,515,763,000
External Customer [Member]
Segment Reporting Information [Line Items]
Interest income	37,785,000	35,591,000
Noninterest income	18,364,000	18,074,000
Total revenue	56,149,000	53,665,000
Interest expense	3,741,000	4,011,000
Noninterest expenses	34,178,000	32,370,000
Provision for loan loss	2,630,000	2,231,000
Total expenses	40,549,000	38,612,000
Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	2,252,000	2,334,000
Noninterest income	1,957,000	1,876,000
Total revenue	4,209,000	4,210,000
Interest expense	2,252,000	2,334,000
Noninterest expenses	1,957,000	1,876,000
Total expenses	4,209,000	4,210,000
WSFS Bank [Member]
Segment Reporting Information [Line Items]
Total revenue	46,885,000	45,380,000
Total expenses	35,205,000	34,173,000
Income before taxes	11,680,000	11,207,000
Capital expenditures	478,000	773,000
WSFS Bank [Member] | External Customer [Member]
Segment Reporting Information [Line Items]
Interest income	35,921,000	33,600,000
Noninterest income	8,395,000	9,227,000
Total revenue	44,316,000	42,827,000
Interest expense	3,630,000	3,840,000
Noninterest expenses	27,612,000	26,430,000
Provision for loan loss	2,323,000	2,246,000
Total expenses	33,565,000	32,516,000
Cash and cash equivalents	78,930,000		73,017,000
Other segment assets	3,917,906,000		3,838,525,000
Total assets	3,996,836,000		3,911,542,000
WSFS Bank [Member] | Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	831,000	903,000
Noninterest income	1,738,000	1,650,000
Total revenue	2,569,000	2,553,000
Interest expense	1,421,000	1,431,000
Noninterest expenses	219,000	226,000
Total expenses	1,640,000	1,657,000
Cash Connect [Member]
Segment Reporting Information [Line Items]
Total revenue	6,207,000	5,227,000
Total expenses	4,467,000	3,913,000
Income before taxes	1,740,000	1,314,000
Capital expenditures	56,000	183,000
Cash Connect [Member] | External Customer [Member]
Segment Reporting Information [Line Items]
Interest income
Noninterest income	6,014,000	5,027,000
Total revenue	6,014,000	5,027,000
Interest expense
Noninterest expenses	3,550,000	2,992,000
Provision for loan loss
Total expenses	3,550,000	2,992,000
Cash and cash equivalents	357,586,000		408,096,000
Other segment assets	2,566,000		1,965,000
Total assets	360,152,000		410,061,000
Cash Connect [Member] | Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income
Noninterest income	193,000	200,000
Total revenue	193,000	200,000
Interest expense	331,000	371,000
Noninterest expenses	586,000	550,000
Total expenses	917,000	921,000
Trust & Wealth Management [Member]
Segment Reporting Information [Line Items]
Total revenue	7,266,000	7,268,000
Total expenses	5,086,000	4,736,000
Income before taxes	2,180,000	2,532,000
Capital expenditures	3,000
Trust & Wealth Management [Member] | External Customer [Member]
Segment Reporting Information [Line Items]
Interest income	1,864,000	1,991,000
Noninterest income	3,955,000	3,820,000
Total revenue	5,819,000	5,811,000
Interest expense	111,000	171,000
Noninterest expenses	3,016,000	2,948,000
Provision for loan loss	307,000	(15,000)
Total expenses	3,434,000	3,104,000
Cash and cash equivalents	3,209,000		3,313,000
Other segment assets	185,765,000		190,847,000
Total assets	188,974,000		194,160,000
Trust & Wealth Management [Member] | Inter-segment Eliminations [Member]
Segment Reporting Information [Line Items]
Interest income	1,421,000	1,431,000
Noninterest income	26,000	26,000
Total revenue	1,447,000	1,457,000
Interest expense	500,000	532,000
Noninterest expenses	1,152,000	1,100,000
Total expenses	$ 1,652,000	$ 1,632,000