Short-Term Borrowings (Narrative) (Detail) (USD $)	12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Short-term Debt [Line Items]
Amount of unsecured letters of credit outstanding		$ 50,000,000
Minimum tangible net worth	275,000,000
Unsecured Credit Facility
Short-term Debt [Line Items]
Total amount available for borrowing	20,000,000	20,000,000
Letters Of Credit [Member]
Short-term Debt [Line Items]
Interest rate of letter of credit	0.50%
Maximum amount available under letter of credit agreement	75,000,000
Letter of credit collateralized marketable securities		71,035,000
Unsecured Revolving Credit Facility
Short-term Debt [Line Items]
Available client securities under customer margin loans to be pledged	328,172,000	329,013,000
Pledged customer securities	26,890,000	18,408,000
Commercial Banking
Short-term Debt [Line Items]
Federal funds rate plus basis points	0.005
Total amount available for borrowing	42,857,000	28,267,000
Southwest Securities [Member] | Uncommitted Credit Facility
Short-term Debt [Line Items]
Broker loan lines	400,000,000
Federal funds rate	0.09%	0.07%
Amount outstanding under credit agreements	59,000,000	86,500,000
Value of collateralized securities	99,202,000	120,568,000
Southwest Securities [Member] | Unsecured Credit Facility
Short-term Debt [Line Items]
Broker loan lines	20,000,000	20,000,000
Amount of unsecured letters of credit outstanding	0	0
Southwest Securities [Member] | Committed Lines Of Credit [Member]
Short-term Debt [Line Items]
Amount of unsecured letters of credit outstanding	0	45,000,000
Agreement with an unaffiliated bank secured, uncommitted revolving credit	45,000,000
Commitment fee	0.00375
Federal funds rate plus basis points	0.0125
Minimum tangible net worth	150,000,000
Collateral of secured borrowings		68,605,000
Option Clearing Corporation [Member]
Short-term Debt [Line Items]
Pledged customer securities	$ 74,326,000