Restructuring (Narrative) (Details) (USD $)	12 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Restructuring Cost and Reserve [Line Items]
Aggregate cost of restructuring plan	$ 20,728,000	$ 29,934,000	$ 15,541,000
Remaining restructuring costs	3,672,000	5,813,000
Comverse First Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Aggregate cost of restructuring plan		7,000,000
Restructuring costs paid	100,000
Comverse Third Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Severance costs recorded	12,600,000	11,600,000
Facilities-related costs	200,000	200,000
Remaining restructuring costs	2,500,000
Netcentrex Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Severance costs recorded	7,600,000	10,900,000
Facilities-related costs	100,000
Remaining restructuring costs	1,200,000
Employee Severance [Member] | Comverse First Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs paid		6,000,000
Employee Severance [Member] | Comverse Third Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs paid	12,400,000	9,100,000
Employee Severance [Member] | Netcentrex Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs paid	9,300,000	8,000,000
Facilities-Related [Member] | Comverse First Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs paid		900,000
Facilities-Related [Member] | Comverse Third Quarter Two Thousand And Ten Initiative [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs paid	$ 300,000	$ 100,000