Securities - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Securities
Realized net gains from trading securities portfolio	$ 39.7	$ 74.2	$ 43.7
Financial Instrument, Owned, Pledged Status [Extensible Enumeration]	Asset Pledged as Collateral	Asset Pledged as Collateral
Asset Pledged as Collateral
Securities
Carrying amount of securities pledged	$ 563.9	$ 537.2
Fair value of securities pledged	520.0	503.1
Hilltop Broker-Dealers
Securities
Realized net gains from trading securities portfolio	$ 88.2	$ 51.9	$ 24.9