Intangible Assets and Goodwill - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment loss of goodwill	$ 137,100	$ 137,100	[1]	$ 0	[1]
Amortization expense		32,400		0		$ 0
Intangible assets not subject to amortization	589,000	$ 589,000		$ 29,000
Nutrisystem, Inc.
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment loss of goodwill	137,100
Nutrisystem, Inc. | Tradename
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment loss of intangibles	$ 240,000

[1] See Note 13 for explanation.