Percentage of economic interest.

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- Definition

Shares Issued During Period, Shares Exchanged For Class A Common Stock

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Balance held at close of period in number of shares.

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- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased and retired during the period.

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Stockholder's Equity - Additional Information (Detail) - USD ($)			3 Months Ended
	Apr. 30, 2019	Nov. 14, 2018	Mar. 31, 2019	Nov. 13, 2018	Aug. 03, 2018
Class of Stock [Line Items]
Stock repurchase program, authorized amount					$ 500,000,000
Pla-Fit Holdings, LLC
Class of Stock [Line Items]
Number of shares exchanged			858,810
Holdings Units
Class of Stock [Line Items]
Number of shares exchanged			858,810
Investor \| Secondary Offering and Exchange
Class of Stock [Line Items]
Number of units held by owners (in shares)			84,462,761
Investor \| Pla-Fit Holdings, LLC \| Secondary Offering and Exchange
Class of Stock [Line Items]
Percentage of economic interest			90.80%
Continuing LLC Owners \| Secondary Offering and Exchange
Class of Stock [Line Items]
Number of units held by owners (in shares)			8,588,920
Continuing LLC Owners \| Pla-Fit Holdings, LLC \| Secondary Offering and Exchange
Class of Stock [Line Items]
Percentage of economic interest			9.20%
Holdings Units
Class of Stock [Line Items]
Shares exchanged for Class A common stock			1
Class A Common Stock
Class of Stock [Line Items]
Number of shares exchanged			858,810
Class A Common Stock \| Investor \| Secondary Offering and Exchange
Class of Stock [Line Items]
Number of units held by owners (in shares)			84,462,761
Class A Common Stock \| Investor \| Pla-Fit Holdings, LLC \| Secondary Offering and Exchange
Class of Stock [Line Items]
Percentage of voting interests acquired			90.80%
Class B Common Stock
Class of Stock [Line Items]
Shares exchanged for Class A common stock			1
Number of shares exchanged			858,810
Class B Common Stock \| Continuing LLC Owners \| Secondary Offering and Exchange
Class of Stock [Line Items]
Number of units held by owners (in shares)			8,588,920
Class B Common Stock \| Continuing LLC Owners \| Pla-Fit Holdings, LLC \| Secondary Offering and Exchange
Class of Stock [Line Items]
Percentage of voting interests acquired			9.20%
ASR Agreement
Class of Stock [Line Items]
Stock repurchase program, authorized amount				$ 300,000,000
Repurchase and retirement of common stock		$ 240,000,000
ASR Agreement \| Class A Common Stock
Class of Stock [Line Items]
Stock repurchased (in shares)		4,607,410
Subsequent event \| ASR Agreement
Class of Stock [Line Items]
Repurchase and retirement of common stock	$ 60,000,000
Subsequent event \| ASR Agreement \| Class A Common Stock
Class of Stock [Line Items]
Stock repurchased (in shares)	524,124