Goodwill, Capitalized Software and Other Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Mar. 31, 2011
Goodwill [Roll Forward]
Goodwill as of beginning of period	$ 607,765
Effect of foreign currency translation	29
Goodwill as of end of period	607,794
Goodwill	607,794
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, amortized intangible assets	394,796		391,214
Accumulated amortization	(318,392)		(312,680)
Net carrying amount, amortized intangible assets	76,404		78,534
Amortization expense of finite-lived intangible assets [Abstract]
Amortization expense	5,732	5,550
Future amortization expense of finite-lived intangible assets [Abstract]
Future amortization expense, year one	22,366
Future amortization expense, year two	17,956
Future amortization expense, year three	13,940
Future amortization expense, year four	8,602
Thereafter	19,273
Application Performance Management [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	282,815
Effect of foreign currency translation	(1)
Goodwill as of end of period	282,814
Goodwill	282,814
Changepoint [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	22,151
Effect of foreign currency translation	0
Goodwill as of end of period	22,151
Goodwill	22,151
Mainframe [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	141,020
Effect of foreign currency translation	0
Goodwill as of end of period	141,020
Goodwill	141,020
Uniface [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	21,350
Effect of foreign currency translation	0
Goodwill as of end of period	21,350
Goodwill	21,350
Professional Services [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	115,044
Effect of foreign currency translation	30
Goodwill as of end of period	115,074
Goodwill	115,074
Application Services [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period	25,385
Effect of foreign currency translation	0
Goodwill as of end of period	25,385
Goodwill	25,385
Products [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period			221,100
Goodwill as of end of period			221,100
Goodwill			221,100
Web Performance Services [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period			219,500
Goodwill as of end of period			219,500
Goodwill			219,500
Former Professional Services [Member]
Goodwill [Roll Forward]
Goodwill as of beginning of period			141,800
Goodwill as of end of period			141,800
Goodwill			141,800
Trademarks [Member]
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, unamortized intangible assets	4,472		4,467
Net carrying amount, unamortized intangible assets	4,472		4,467
Capitalized Software [Member]
Future amortization expense of finite-lived intangible assets [Abstract]
Future amortization expense, year one	16,681
Future amortization expense, year two	13,634
Future amortization expense, year three	10,112
Future amortization expense, year four	4,814
Thereafter	2,813
Capitalized Software [Member] | Internally Developed [Member]
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, amortized intangible assets	198,376		194,770
Accumulated amortization	(164,659)		(161,671)
Net carrying amount, amortized intangible assets	33,717		33,099
Amortized over periods	5
Amortization expense of finite-lived intangible assets [Abstract]
Amortization expense	2,975	2,738
Capitalized Software [Member] | Purchased [Member]
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, amortized intangible assets	136,462		136,469
Accumulated amortization	(126,288)		(125,118)
Net carrying amount, amortized intangible assets	10,174		11,351
Amortized over periods	5
Amortization expense of finite-lived intangible assets [Abstract]
Amortization expense	1,182	1,216
Customer Relationship [Member]
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, amortized intangible assets	48,795		48,813
Accumulated amortization	(17,795)		(16,729)
Net carrying amount, amortized intangible assets	31,000		32,084
Amortized over periods	10
Amortization expense of finite-lived intangible assets [Abstract]
Amortization expense	1,087	1,130
Future amortization expense of finite-lived intangible assets [Abstract]
Future amortization expense, year one	4,212
Future amortization expense, year two	3,835
Future amortization expense, year three	3,788
Future amortization expense, year four	3,788
Thereafter	16,460
Others [Member]
Capitalized Software and Other Intangible Assets [Abstract]
Gross carrying amount, amortized intangible assets	11,163		11,162
Accumulated amortization	(9,650)		(9,162)
Net carrying amount, amortized intangible assets	1,513		2,000
Amortized over periods	3
Amortization expense of finite-lived intangible assets [Abstract]
Amortization expense	488	466
Future amortization expense of finite-lived intangible assets [Abstract]
Future amortization expense, year one	1,473
Future amortization expense, year two	487
Future amortization expense, year three	40
Future amortization expense, year four	0
Thereafter	$ 0