Legal and Other Proceedings - Additional Information (Detail) - USD ($)		6 Months Ended
Jul. 07, 2016	Jun. 30, 2016
Loss Contingencies [Line Items]
Additions to other significant pending legal or other proceedings		$ 0
Subsequent Event [Member]
Loss Contingencies [Line Items]
Legal fees for counsel to plaintiffs	$ 335,000
Goldstein Case [Member]
Loss Contingencies [Line Items]
Disputed amount		5,000,000
Amount payable upon proposed settlement		$ 1,450,000

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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

No definition available.

+ Details

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

+ Details

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- Definition

Additions To Other Significant Pending Legal Or Other Proceedings

+ References

No definition available.

+ Details

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- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationCaseAxis=wsfs_GoldsteinCaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: