Short-term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Short-term borrowings
Short-term borrowings	$ 753,777		$ 1,417,289
Hilltop Broker-Dealers
Short-term borrowings
Weighted average interest rate (as a percent)	1.84%		1.59%
Federal funds purchased.
Short-term borrowings
Short-term borrowings	$ 112,350		$ 87,125
Securities sold under agreement to repurchase.
Short-term borrowings
Short-term borrowings	364,927		195,164
FHLB notes
Short-term borrowings
Short-term borrowings	150,000		$ 1,000,000
Average balance during the period	$ 180,000	$ 234,341
Average interest rate during the period (as a percent)	0.61%	0.44%
Average interest rate at end of period (as a percent)	0.90%		0.55%
FHLB notes | Maximum
Short-term borrowings
Maturity term of debt	365 days
Short-term bank loans.
Short-term borrowings
Short-term borrowings	$ 126,500		$ 135,000
Federal funds purchased and securities sold under agreements to repurchase.
Short-term borrowings
Average balance during the period	$ 386,624	$ 329,392
Average interest rate during the period (as a percent)	0.76%	0.49%
Average interest rate at end of period (as a percent)	0.69%		0.42%
Carrying value	$ 371,859		$ 209,877
Estimated fair value	$ 379,390		$ 206,641