Goodwill and Intangibles - Schedule of Allocation of Goodwill to Our Reportable Operating Segments for Purposes of Goodwill Impairment Testing (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Goodwill [Line Items]
Goodwill, Beginning balance	$ 85,212
Changes in goodwill	(358)	$ 173
Goodwill, Ending balance	84,854	85,212
WSFS Bank [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	80,078
Changes in goodwill	(358)
Goodwill, Ending balance	79,720	$ 80,078
Trust & Wealth Management [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	5,134
Goodwill, Ending balance	$ 5,134

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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