Equity Attributable To Comverse Technology, Inc. And Noncontrolling Interest (Components Of Equity Attributable To Comverse Technology, Inc.'s And Its Noncontrolling Interest) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2011	Oct. 31, 2010
Equity [Line Items]
Balance, January 31			$ 485,887	$ 509,722
Net loss	42,267	(31,506)	(46,740)	(138,131)
Unrealized gains and losses on available-for-sale securities, net of reclassification adjustments and tax			(4,443)	(10,792)
Unrealized gains and losses for cash flow hedge positions, net of reclassification adjustments and tax			(373)	2,530
Foreign currency translation adjustment			(1,960)	(3,961)
Total comprehensive loss			(53,516)	(150,354)
Stock-based compensation expense			7,150	8,152
Exercises of stock options			1,861
Impact from equity transactions of subsidiaries and other			27,303	50,999
Repurchase of common stock			(4,319)	(480)
Balance, October 31	464,366	418,039	464,366	418,039
Comverse Technology, Inc.'s Shareholders' Equity [Member]
Equity [Line Items]
Balance, January 31			413,008	422,486
Net loss			(63,202)	(147,751)
Unrealized gains and losses on available-for-sale securities, net of reclassification adjustments and tax			(4,443)	(10,768)
Unrealized gains and losses for cash flow hedge positions, net of reclassification adjustments and tax			(216)	2,111
Foreign currency translation adjustment			(166)	(2,018)
Total comprehensive loss			(68,027)	(158,426)
Stock-based compensation expense			7,150	8,152
Exercises of stock options			1,861
Impact from equity transactions of subsidiaries and other			15,268	56,547
Repurchase of common stock			(4,319)	(480)
Balance, October 31	364,941	328,279	364,941	328,279
Noncontrolling Interest [Member]
Equity [Line Items]
Balance, January 31			72,879	87,236
Net loss			16,462	9,620
Unrealized gains and losses on available-for-sale securities, net of reclassification adjustments and tax				(24)
Unrealized gains and losses for cash flow hedge positions, net of reclassification adjustments and tax			(157)	419
Foreign currency translation adjustment			(1,794)	(1,943)
Total comprehensive loss			14,511	8,072
Impact from equity transactions of subsidiaries and other			12,035	(5,548)
Balance, October 31	$ 99,425	$ 89,760	$ 99,425	$ 89,760