PROPERTY AND EQUIPMENT: (Details) (USD $)	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Property and Equipment
Property and equipment, gross	$ 852,236,000	$ 822,439,000
Less accumulated depreciation and amortization	635,330,000	591,687,000
Property and equipment, net	216,906,000	230,752,000
Depreciation expense on property and equipment	58,300,000	61,800,000	62,400,000
Land
Property and Equipment
Property and equipment, gross	6,737,000	6,737,000
Buildings and improvements
Property and Equipment
Property and equipment, gross	273,451,000	263,172,000
Data processing equipment
Property and Equipment
Property and equipment, gross	520,927,000	492,626,000
Office furniture and other equipment
Property and Equipment
Property and equipment, gross	$ 51,121,000	$ 59,904,000