Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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Sources of Revenue and Other Information by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Oct. 03, 2015	Jul. 04, 2015	Apr. 04, 2015	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Meeting Fees									$ 605,332	$ 587,801	$ 744,560
Online Subscription Revenues									343,789	349,567	437,385
In-meeting product sales									125,508	127,291	169,101
Licensing, franchise royalties and other									90,273	99,760	128,870
Net revenue	$ 267,412	$ 280,819	$ 309,761	$ 306,910	$ 259,238	$ 273,324	$ 309,754	$ 322,103	1,164,902	1,164,419	1,479,916
Long-lived assets	49,574				58,186				49,574	58,186	74,650
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue									743,668	700,972	869,541
Long-lived assets	43,714				51,103				43,714	51,103	67,903
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue									55,159	54,277	78,175
Long-lived assets	2,730				2,757				2,730	2,757	3,149
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue									100,808	124,773	156,843
Long-lived assets	1,899				2,938				1,899	2,938	724
Continental Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue									210,590	229,147	298,878
Long-lived assets	716				614				716	614	1,454
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue									54,677	55,250	76,479
Long-lived assets	$ 515				$ 774				$ 515	$ 774	$ 1,420