Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 98,079	$ 116,598
Membership dues
Disaggregation of Revenue [Line Items]
Revenues	74,592	88,823
Initiation and processing fees
Disaggregation of Revenue [Line Items]
Revenues	146	429
Membership revenue
Disaggregation of Revenue [Line Items]
Revenues	74,738	89,252
Personal training revenue
Disaggregation of Revenue [Line Items]
Revenues	16,391	19,489
Other ancillary club revenue
Disaggregation of Revenue [Line Items]
Revenues	5,680	6,399
Ancillary club revenue
Disaggregation of Revenue [Line Items]
Revenues	22,071	25,888
Fees and other revenue
Disaggregation of Revenue [Line Items]
Revenues	$ 1,270	$ 1,458

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration