CONSOLIDATED STATEMENTS OF NET INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Income Statement [Abstract]
Service revenues, net	$ 283,001	$ 251,550	$ 544,477	$ 495,318
Product sales and other, net	58,672	58,211	126,259	121,353
Revenues, net	341,673	309,761	670,736	616,671
Cost of services	120,325	119,758	245,210	244,430
Cost of product sales and other	32,335	28,955	72,416	61,520
Cost of revenues	152,660	148,713	317,626	305,950
Gross profit	189,013	161,048	353,110	310,721
Marketing expenses	41,968	41,199	128,397	127,714
Selling, general and administrative expenses	50,839	46,118	98,273	95,720
Operating income	96,206	73,731	126,440	87,287
Interest expense	27,092	28,609	55,234	58,634
Other (income) expense, net	(488)	607	154	542
Gain on early extinguishment of debt	(1,554)	0	(1,554)	0
Income before income taxes	71,156	44,515	72,606	28,111
Provision for income taxes	25,992	14,034	16,864	8,431
Net income	45,164	30,481	55,742	19,680
Net loss attributable to the noncontrolling interest	9	13	83	61
Net income attributable to Weight Watchers International, Inc.	$ 45,173	$ 30,494	$ 55,825	$ 19,741
Earnings Per Share attributable to Weight Watchers International, Inc.
Basic	$ 0.70	$ 0.48	$ 0.87	$ 0.31
Diluted	$ 0.67	$ 0.46	$ 0.83	$ 0.30
Weighted average common shares outstanding
Basic	64,269	63,740	64,124	63,644
Diluted	67,737	65,934	67,304	65,890

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate cost of goods produced and sold and services rendered during the reporting period.