Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Supplemental Cash Flow Information [Abstract]
Net loss of discontinued operations	$ 0	$ 11,039	$ 43,062
Depreciation and amortization	88,082	88,592	101,189
Impairment of goodwill and other intangible assets	0	0	3,356
Other than Temporary Impairment Losses, Investments	0	407	6,914
Impairment of UBS put	0	6,696	6,889
Loss on extinguishment of debt	8,136	0	0
Provision for doubtful accounts	5,869	1,511	3,534
Stock-based compensation expense	30,904	39,321	44,623
Excess tax benefits from stock award plans	(847)	(815)	0
Operating asset write-downs	2,601	1,257	6,423
Deferred income taxes	36,945	43,011	(35,005)
Net realized gains on sale of investments	(24,414)	(23,810)	(10,788)
Equity in losses of unconsolidated affiliates, net of tax	(64)	20	6
Gains on sale of assets	(67)	(2,774)	0
Provision for inventory reserves	5,114	13,038	8,397
Losses on derivative financial instruments	611	5,385	13,612
Foreign currency transaction (gains) losses	(2,332)	(1,932)	785
Other non-cash items, net	(1,770)	1,017	1,321
Net non-cash operating items—continuing operations	148,768	181,963	194,318
Accrued but unpaid purchases of property and equipment	520	1,670	1,935
Inventory transfers to property and equipment	18,827	4,336	3,481
Liabilities for contingent consideration in business combinations	42,404	3,424	0
Settlement of shareholder class action lawsuit with CTI common stock	82,500	0	0
Cash paid during the year for interest—continuing operations	29,250	21,056	24,705
Cash paid during the year for income taxes—continuing operations	$ 21,946	$ 14,225	$ 20,158