Schedule II. Condensed Financial Statements of Parent Company (Condensed Balance Sheets) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	25,082,104	25,055,479
Common stock, shares outstanding (in shares)	25,082,104	25,055,479
United Fire Group, Inc.
Condensed Balance Sheet Statements, Captions [Line Items]
Fixed maturities, Available-for-sale securities, amortized cost	$ 150	$ 150
Common stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	25,082,104	25,055,479
Common stock, shares outstanding (in shares)	25,082,104	25,055,479