Earnings (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
	Apr. 30, 2012	Apr. 30, 2011
Earnings Per Share [Abstract]
Net loss attributable to Comverse Technology, Inc. - basic	$ (53,210)	$ (59,195)
Adjustment for subsidiary stock options	(74)	(2)
Net loss attributable to Comverse Technology, Inc. - diluted	$ (53,284)	$ (59,197)
Basic and diluted weighted average common shares outstanding (in shares)	218,855,000	205,700,000
Basic and Diluted (in dollars per share)	$ (0.24)	$ (0.29)
Contingently issuable shares excluded from computation of diluted earnings per share	500,000	800,000