Stockholders' Equity - Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pro forma earnings per share:
Income (loss) before taxes	$ 2,374	$ 2,793	$ (58)	$ 4,769
Less: income (loss) before taxes attributable to non-controlling interests	1,061	1,332	(18)	2,288
Income (loss) before taxes attributable to GSHD	1,313	1,461	(40)	2,481
Less: income tax expense (benefit) attributable to GSHD	(666)	(2,575)	(104)	(2,646)
Net income attributable to GSHD	$ 1,979	$ 4,036	$ 64	$ 5,127
Weighted average shares of Class A common stock outstanding - basic (in shares)	20,892	19,559	20,531	18,903
Effect of dilutive securities, stock options (in shares)	677	1,647	899	1,667
Weighted average shares of Class A common stock outstanding - diluted (in shares)	21,569	21,206	21,430	20,570
Earnings per share of Class A common stock - basic (in dollars per share)	$ 0.09	$ 0.21	$ 0	$ 0.27
Earnings per share of Class A common stock - diluted (in dollars per share)	$ 0.09	$ 0.19	$ 0	$ 0.25
Antidilutive securities excluded from computation of earnings per share (in shares)	2,388	41	1,947	66
Class A Common stock
Pro forma earnings per share:
Earnings per share of Class A common stock - basic (in dollars per share)	$ 0.09	$ 0.21	$ 0	$ 0.27
Earnings per share of Class A common stock - diluted (in dollars per share)	$ 0.09	$ 0.19	$ 0	$ 0.25