Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Reconciliation of Numerators and Denominators Used to Compute Basic and Diluted Earnings per Share

The following table sets forth reconciliations used to compute basic and diluted earnings per share of Class A common stock:  

	Three months ended June 30,				Six months ended June 30,
	2018		2017		2018		2017
Numerator
Net income	$	30,418	$	18,004	$	53,912	$	35,870
Less: net income attributable to non-controlling interests	4,544		5,592		8,157		14,616
Net income attributable to Planet Fitness, Inc.	$	25,874	$	12,412	$	45,755	$	21,254
Denominator
Weighted-average shares of Class A common stock outstanding - basic	87,693,377		79,153,778		87,564,596		71,678,755
Effect of dilutive securities:
Stock options	389,994		33,564		351,987		28,893
Restricted stock units	21,960		5,708		14,886		5,121
Weighted-average shares of Class A common stock outstanding - diluted	88,105,331		79,193,050		87,931,469		71,712,769
Earnings per share of Class A common stock - basic	$	0.30	$	0.16	$	0.52	$	0.30
Earnings per share of Class A common stock - diluted	$	0.29	$	0.16	$	0.52	$	0.30