FOREIGN OPERATIONS: (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Financial information by geographic area
Revenues	$ 257,367	$ 260,440	$ 260,037	$ 242,215	$ 268,562	$ 268,761	$ 267,777	$ 257,178	$ 1,020,059	$ 1,062,278	$ 1,068,158
Long-lived assets excluding financial instruments	908,370				657,776				908,370	657,776
United States
Financial information by geographic area
Revenues									924,281	949,898	954,467
Long-lived assets excluding financial instruments	875,276				617,668				875,276	617,668
Foreign
Financial information by geographic area
Revenues									95,778	112,380	113,691
Long-lived assets excluding financial instruments	33,094				40,108				33,094	40,108
Europe
Financial information by geographic area
Revenues									59,958	73,294	74,077
Long-lived assets excluding financial instruments	11,467				13,886				11,467	13,886
Asia/ Pacific
Financial information by geographic area
Revenues									32,658	34,540	34,876
Long-lived assets excluding financial instruments	20,683				24,912				20,683	24,912
Other
Financial information by geographic area
Revenues									3,162	4,546	4,738
Long-lived assets excluding financial instruments	$ 944				$ 1,310				$ 944	$ 1,310