Loss Per Share Attributable to Comverse Technology, Inc.'s Shareholders (Schedule Of Calculation Of Earnings (Loss) Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2010	Jul. 31, 2010	Apr. 30, 2010	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Earnings Per Share [Abstract]
Net income (loss) from continuing operations attributable to Comverse Technology, Inc. - basic									$ (58,726)	$ (125,617)	$ (230,430)
Adjustment for subsidiary stock options									(229)	(254)	(178)
Net income (loss) from continuing operations attributable to Comverse Technology, Inc. - diluted									(58,955)	(125,871)	(230,608)
Net loss from discontinued operations, attributable to Comverse Technology, Inc.-basic and diluted.					$ (3,707)	$ (774)	$ (1,000)	$ (1,224)	$ 0	$ (6,705)	$ (41,605)
Basic weighted average common shares outstanding	208,302,000				205,163,000				208,302,000	205,163,000	204,513,000
Earnings (loss) per share from continuing operations attributable to Comverse Technology, Inc., Basic					$ 0.10	$ (0.20)	$ (0.12)	$ (0.39)	$ (0.28)	$ (0.61)	$ (1.13)
Loss per share from discontinued operations attributable to Comverse Technology, Inc., Basic					$ (0.02)	$ 0.00	$ 0.00	$ (0.01)	$ 0.00	$ (0.03)	$ (0.20)
Basic loss per share	$ 0.02	$ 0.17	$ (0.19)	$ (0.29)	$ 0.08	$ (0.20)	$ (0.12)	$ (0.40)	$ (0.28)	$ (0.64)	$ (1.33)
Earnings (loss) per share from continuing operations attributable to Comverse Technology, Inc., Diluted					$ 0.09	$ (0.21)	$ (0.12)	$ (0.39)	$ (0.28)	$ (0.62)	$ (1.13)
Loss per share from discontinued operations attributable to Comverse Technology, Inc., Diluted					$ (0.02)	$ 0.00	$ 0.00	$ (0.01)	$ 0.00	$ (0.03)	$ (0.20)
Diluted loss per share	$ 0.02	$ 0.17	$ (0.19)	$ (0.29)	$ 0.07	$ (0.21)	$ (0.12)	$ (0.40)	$ (0.28)	$ (0.65)	$ (1.33)
Contingently issuable shares excluded from computation of diluted earnings per share									800,000	900,000	700,000