Segment Information - Details of Segment Information- Statement of Financial Condition (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Cash and cash equivalents	$ 745,311	$ 821,923	$ 703,893	$ 561,179
Goodwill	166,007	167,539	84,852
Other segment assets	5,911,109		5,045,362
Total assets	6,822,427	6,765,270	5,834,107
WSFS Bank
Segment Reporting Information [Line Items]
Cash and cash equivalents	96,306		84,919
Goodwill	145,808	147,396	79,718
Other segment assets	5,690,046		4,843,166
Total assets	5,932,160		5,007,803
Cash Connect
Segment Reporting Information [Line Items]
Cash and cash equivalents	643,506		617,339
Goodwill	0	$ 0	0
Other segment assets	5,018		3,419
Total assets	648,524		620,758
Wealth Management
Segment Reporting Information [Line Items]
Cash and cash equivalents	5,499		1,635
Goodwill	20,199		5,134
Other segment assets	216,045		198,777
Total assets	$ 241,743		$ 205,546