Organization and Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 15, 2020	Jun. 25, 2018	Jun. 30, 2021
i3Verticals, LLC
Subsidiary, Sale of Stock [Line Items]
Non-controlling interest, ownership interest (percent)			68.20%
Continuing Equity Owner
Subsidiary, Sale of Stock [Line Items]
Shareholders ownership interest (percent)			32.40%
Class A Common Stock | Continuing Equity Owner
Subsidiary, Sale of Stock [Line Items]
Shareholders ownership interest (percent)			0.60%
Class B Common Stock | Continuing Equity Owner
Subsidiary, Sale of Stock [Line Items]
Shareholders ownership interest (percent)			31.80%
IPO
Subsidiary, Sale of Stock [Line Items]
Shares issued (shares)		7,647,500
Public offering price (in USD per share)		$ 13.00
Net proceeds from public offering		$ 92,500
Primary Public Offering | i3Verticals, LLC
Subsidiary, Sale of Stock [Line Items]
Net proceeds from public offering	$ 72,018
Common units, purchased (in units)	3,250,000
Primary Public Offering | Continuing Equity Owner
Subsidiary, Sale of Stock [Line Items]
Common units, purchased (in units)	487,500
Primary Public Offering | Class A Common Stock
Subsidiary, Sale of Stock [Line Items]
Shares issued (shares)	3,737,500
Public offering price (in USD per share)	$ 23.50
Net proceeds from public offering	$ 83,400
Underwriters exercised option to purchase additional shares (shares)	487,500