Stockholders' Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified		0 Months Ended	12 Months Ended		0 Months Ended									12 Months Ended
	Dec. 31, 2012	Sep. 27, 2011 Series B Preferred Stock	Dec. 31, 2012 Series B Preferred Stock item	Dec. 31, 2011 Series B Preferred Stock	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on December 1, 2012 and ending on December 31, 2012	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on January 1, 2013 and ending on March 31, 2013	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on April 1, 2013 and ending on December 31, 2013 Minimum	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on April 1, 2013 and ending on December 31, 2013 Maximum	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on January 1, 2014 and ending on March 26, 2016 Minimum	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on January 1, 2014 and ending on March 26, 2016 Maximum	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on March 27, 2016 ending on redemption	Dec. 30, 2012 Series B Preferred Stock Dividend period beginning on January 1, 2014 and ending on April 1, 2016	Dec. 20, 2010 Series A Preferred Stock	Dec. 31, 2004 Series A Preferred Stock	Sep. 06, 2010 Series A Preferred Stock	Feb. 18, 2009 Series A Preferred Stock	Dec. 20, 2010 Preferred Stock	Nov. 30, 2012 Plains Capital	Nov. 30, 2012 Plains Capital Series B Preferred Stock
Stockholders' Equity
Amount of retained earnings available for dividend declaration without prior regulatory approval	$ 13.9
Stockholders' Equity
Number of shares of Hilltop Series B Preferred Stock into which each outstanding share of PlainsCapital Non-Cumulative Perpetual Preferred Stock, Series C is converted																		1	1
Annualized Dividend Rate (as a percent)					2.73%	2.468%	1.00%	5.00%	1.00%	5.00%	9.00%		8.25%	8.25%
Quarterly lending incentive fee as a percentage of the liquidation value												0.50%
Number of quarters after failure to declare and pay dividends on Series B Preferred Stock for which the entity may not pay dividends to common stockholders nor may repurchase or redeem any shares of common stock			3
Tier 1 Dividend Threshold (as a percent)		90.00%
Redemption price as a percentage of the liquidation amount			100.00%
Preferred Stock issued														5,000,000
Offering price (in dollars per share)														$ 25.00
Liquidation preference (in dollars per share)			$ 1,000.00	$ 1,000.00										$ 25.00
Cash redemption price (in dollars per share)															$ 25.2063	$ 25.00
Number of Series A Cumulative Redeemable Preferred Stock reclassified and designated as preferred stock													(750,000)				750,000