Goodwill and Intangibles - Schedule of Allocation of Goodwill to Our Reportable Operating Segments for Purposes of Goodwill Impairment Testing (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Goodwill [Line Items]
Goodwill, Beginning balance	$ 48,651
Changes in goodwill	136	$ 46
Goodwill, Ending balance	48,787
WSFS Bank [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	43,517
Changes in goodwill	136
Goodwill, Ending balance	43,653
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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- Details

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