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Investment, Ownership Interest

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Minimum For Notes Repayment, Refinanced, Converted, Discharged, or Prepaid, For Maturity Date Extension Trigger

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Number Of Joint Ventures

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Payments for Excess Cash Flows

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Proceeds For Investment In Newly Formed Joint Venture

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Amount of short-term and long-term debt and lease obligation.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The number of countries in which the entity operates as of balance sheet date.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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NATURE OF BUSINESS - Narrative (Details)			1 Months Ended			3 Months Ended	12 Months Ended	36 Months Ended	48 Months Ended
NATURE OF BUSINESS - Narrative (Details)	Mar. 11, 2019 USD ($)	Feb. 28, 2018 USD ($)	Apr. 30, 2020 USD ($)	Mar. 31, 2019 USD ($)	Feb. 28, 2019 joint_ventures	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) segment country	Dec. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Jul. 01, 2023 USD ($)	Mar. 25, 2020 USD ($)	Dec. 31, 2018 USD ($)
Number of reportable segments \| segment							3
Number of international countries in which franchise stores are located \| country							50
Number of joint ventures \| joint_ventures					2
Total debt							$ 862,565,000					$ 1,152,322,000
Subsequent Event \| Revolving Credit Facility
Letters of credit outstanding											$ 30,000,000
JV Framework Agreement
Equity method investment, ownership percentage					35.00%
IVC Joint Venture
Proceeds for investment in newly formed joint venture	$ 101,000,000			$ 99,200,000		$ 101,000,000
IVC Joint Venture \| Subsequent Event \| Forecast
Equity method investment, ownership percentage								100.00%		100.00%
Expected annual proceeds for investment in newly formed joint venture										$ 18,800,000
Proceeds for investment in newly formed joint venture								$ 75,000,000.0	$ 75,000,000	$ 75,000,000.0
IVC Joint Venture \| International Vitamin Corporation
Ownership interest (percentage)				43.00%
Term Loan Facility Due March 2019
Total debt		$ 1,131,200,000
Revolving Credit Facility
Total debt		225,000,000.0
Term Loan
Total debt							0					147,289,000
Term Loan \| Amended Term Loan Facility Due March 2021
Total debt		704,300,000
Term Loan \| Amended Term Loan Facility Due March 2021 \| Tranche B-2
Total debt							441,500,000					554,760,000
Term Loan \| Term Loan Facility Due March 2019
Minimum for notes repayment, refinanced, converted, discharged, or prepaid, For maturity date extension trigger		$ 50,000,000
Term Loan \| Reduced Rate \| Amended Term Loan Facility Due March 2021 \| Tranche B-2
Payments for excess cash flows							25,900,000
Term Loan \| Reduced Rate \| Amended Term Loan Facility Due March 2021 \| Tranche B-2 \| Forecast
Payments for excess cash flows			$ 25,900,000
Notes \| 1.5% Convertible Senior Notes Due 2020
Total debt							154,675,000					$ 175,504,000
Letter of Credit \| FILO Term Loan \| Revolving Credit Facility
Letters of credit outstanding							$ 4,900,000