OTHER CURRENT AND NONCURRENT ASSETS: (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Mar. 31, 2011
Other current assets
Prepaid expenses	$ 39,186	$ 40,478
Assets of non-qualified retirement plan	12,096	12,840
Other miscellaneous assets	763	2,350
Total other current assets	52,045	55,668
Other noncurrent assets
Acquired intangible assets, net	2,229	6,896
Other miscellaneous noncurrent assets	2,177	2,828
Total other assets	$ 4,406	$ 9,724