Regulatory Matters - Net Capital Position, Broker-Dealers (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Net Capital
Amount required to be segregated in cash and securities for the benefit of customers	$ 207,336	$ 180,993
Hilltop Securities
Net Capital
Net capital	181,288
Less required net capital	9,679
Excess net capital	$ 171,609
Net capital as a percentage of aggregate debit items	37.50%
Net capital in excess of 5% aggregate debt items	$ 157,089
Amount required to be segregated in cash and securities for the benefit of customers	207,300	$ 181,000
HTS Independent Network
Net Capital
Net capital	3,353
Less required net capital	250
Excess net capital	$ 3,103