Non-controlling interest - Effect of changes in ownership interests on equity (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Noncontrolling Interest [Line Items]
Net income attributable to Goosehead Insurance Inc.	$ 1,979			$ 4,036			$ 64	$ 5,127
Decrease in additional paid-in capital as a result of the redemption of LLC interests	0	$ 0	$ 0	0	$ 0	$ 0
Increase in additional paid-in capital as a result of activity under employee stock purchase plan	165	177	214	194	214	205
Parent
Noncontrolling Interest [Line Items]
Net income attributable to Goosehead Insurance Inc.	1,979			4,036			64	5,127
Decrease in additional paid-in capital as a result of the redemption of LLC interests	(1,579)	(377)	(344)	(1,144)	(1,280)	(249)	(2,300)	(2,673)
Increase in additional paid-in capital as a result of activity under employee stock purchase plan	165	$ 177	$ 214	194	$ 214	$ 205	556	613
Total effect of changes in ownership interest on equity attributable to Goosehead Insurance Inc.	$ 565			$ 3,086			$ (1,680)	$ 3,067