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Acquisition of Weilos and Miami Franchise - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 27, 2016	Mar. 11, 2015	Oct. 01, 2016	Jan. 02, 2016
Business Acquisition
Goodwill			$ 167,638	$ 159,331
Weilos
Business Acquisition
Business acquisition, purchase price allocation, net purchase price		$ 6,674
Business acquisition, purchase price allocation, common stock issued		2,810
Business acquisition, purchase price allocation, restricted stock issued		114
Business acquisition, net purchase price		2,775
Business acquisition, purchase price allocation, cash reserves		975
Goodwill		5,588
Business acquisition, purchase price allocation, finite lived intangible assets		1,741
Business acquisition, purchase price allocation, fixed assets		24
Business acquisition, purchase price allocation, deferred tax liabilities		679
Restricted shares issued to key employees		$ 908
Weight Watchers of Greater Miami, Inc.
Business Acquisition
Business acquisition, purchase price allocation, net purchase price	$ 3,250
Business acquisition, net purchase price	2,898
Goodwill	2,945
Business acquisition, cash reserves	300
Business acquisition, assumed net liabilities	52
Weight Watchers of Greater Miami, Inc. \| Customer Relationships
Business Acquisition
Business acquisition, purchase price allocation, finite lived intangible assets	191
Weight Watchers of Greater Miami, Inc. \| Franchise Rights
Business Acquisition
Business acquisition, purchase price allocation, indefinite lived intangible assets	$ 114