Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Basis Of Presentation [Line Items]

+ References

No definition available.

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- Definition

Number Of Office Locations

+ References

No definition available.

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- Definition

Number of Unconsolidated Affiliate

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Wholly Owned Subsidiaries Of Company

+ References

No definition available.

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- Details

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Basis of Presentation - Additional Information (Detail)	6 Months Ended
Basis of Presentation - Additional Information (Detail)	Jun. 30, 2017 Subsidiary Office	Jun. 13, 2016 USD ($)	Dec. 31, 2012 USD ($)
Basis Of Presentation [Line Items]
Number of unconsolidated affiliate	1
Number of banking offices	76
Senior Unsecured Fixed - to - Floating Rate Notes
Basis Of Presentation [Line Items]
Senior unsecured fixed-to-floating rate notes, issued amount \| $		$ 100,000,000
Interest rate on unsecured debt		4.50%
Senior unsecured notes, redemption price percentage of principal	100.00%
Senior Unsecured Fixed - to - Floating Rate Notes \| London Interbank Offered Rate (LIBOR)
Basis Of Presentation [Line Items]
Senior unsecured notes, variable rate added to LIBOR	3.30%
Delaware
Basis Of Presentation [Line Items]
Number of banking offices	45
Pennsylvania
Basis Of Presentation [Line Items]
Number of banking offices	29
Virginia
Basis Of Presentation [Line Items]
Number of banking offices	1
Nevada
Basis Of Presentation [Line Items]
Number of banking offices	1
WSFS Financial Corporation
Basis Of Presentation [Line Items]
Number of wholly-owned subsidiaries \| Subsidiary	3
Senior notes due 2019
Basis Of Presentation [Line Items]
Senior unsecured fixed-to-floating rate notes, issued amount \| $			$ 55,000,000.0
Interest rate on unsecured debt			6.25%