Revenue Recognition - Additional Information (Details)			3 Months Ended		4 Months Ended	6 Months Ended
		Mar. 07, 2019 Segment	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Segment Program Obligation Source	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Disaggregation Of Revenue [Line Items]
Number of reportable segments | Segment		1				2
Revenue, Practical Expedient, Initial Application and Transition, Qualitative Assessment						true
Revenue	[1]		$ 262,598,000	$ 340,377,000		$ 600,253,000	$ 554,471,000
Healthcare
Disaggregation Of Revenue [Line Items]
Number of programs | Program						3
Number of performance obligations | Obligation						1
Number of performance obligation unsatisfied | Obligation						0
Revenue recognized from performance obligations satisfied in prior period			0			$ 0
Period of billing in arrears once timing of services to customers is known						1 month
Number of days for customer to make payment after being invoiced						30 days
Capitalized costs			700,000			$ 700,000		$ 500,000
Number of reportable segments | Segment						2
Revenue			81,923,000	157,481,000		$ 241,615,000	314,008,000
Nutrition
Disaggregation Of Revenue [Line Items]
Number of sources for revenue recognition | Source						4
Description of return of obligation						Direct to consumer customers may return unopened ready-to-go Nutrisystem products within 30 days after purchase in order to receive a refund or credit.
Return of purchase order to refund or credit, period						30 days
Purchase order canceled of delivery, period						14 days
Revenue			180,675,000	182,896,000		$ 358,638,000	$ 240,463,000
Provision for estimated returns			4,100,000	5,600,000	$ 7,000,000.0	9,300,000
Nutrition | Accrued Liabilities
Disaggregation Of Revenue [Line Items]
Reserve for estimated returns			1,400,000			1,400,000		$ 800,000
Nutrition | Shipping and Handling Charges
Disaggregation Of Revenue [Line Items]
Revenue			$ 6,500,000	$ 6,300,000	$ 8,100,000	$ 13,000,000.0

[1] The figure for total segments equals the consolidated figure for such item.