Condensed consolidated statements of comprehensive income (loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income including non-controlling interests	$ 29,692	$ 20,472	$ 101,158	$ 74,384
Other comprehensive income (loss), net:
Unrealized gain on interest rate caps, net of tax	0	606	0	989
Foreign currency translation adjustments	(62)	40	95	(23)
Total other comprehensive income, net	(62)	646	95	966
Total comprehensive income including non-controlling interests	29,630	21,118	101,253	75,350
Less: total comprehensive income attributable to non-controlling interests	3,915	3,007	13,128	11,221
Total comprehensive income attributable to Planet Fitness, Inc.	$ 25,715	$ 18,111	$ 88,125	$ 64,129