Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Mar. 31, 2011
Segment Information [Abstract]
Number of reportable business segments	6		6		4
Segment Reporting Information [Line Items]
Software license fees	$ 61,711	$ 45,613	$ 95,837	$ 78,943
Maintenance and subscription fees	128,181	122,007	254,290	238,766
Professional services fees	70,804	58,249	140,543	114,645
Total revenues	260,696	225,869	490,670	432,354
Operating expenses	222,536	185,008	432,893	369,106
Income (loss) from operations	38,160	40,861	57,777	63,248
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	260,696	225,869	490,670	432,354
Long-lived assets	1,207,632		1,207,632		985,381
Number of reportable business segments into which the former products segment was split	4		4
Application Performance Management [Member]
Segment Reporting Information [Line Items]
Software license fees	18,329	18,229	29,782	32,461
Maintenance and subscription fees	37,728	33,201	74,822	61,646
Professional services fees	6,787	5,309	13,753	9,467
Total revenues	62,844	56,739	118,357	103,574
Operating expenses	79,932	57,282	149,371	114,077
Income (loss) from operations	(17,088)	(543)	(31,014)	(10,503)
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	62,844	56,739	118,357	103,574
Mainframe [Member]
Segment Reporting Information [Line Items]
Software license fees	38,456	22,761	57,154	37,469
Maintenance and subscription fees	78,019	77,886	154,994	155,627
Professional services fees	1,569	1,488	3,402	3,134
Total revenues	118,044	102,135	215,550	196,230
Operating expenses	24,129	23,420	48,205	47,172
Income (loss) from operations	93,915	78,715	167,345	149,058
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	118,044	102,135	215,550	196,230
Changepoint [Member]
Segment Reporting Information [Line Items]
Software license fees	2,136	2,248	4,130	4,600
Maintenance and subscription fees	4,415	3,611	8,717	7,162
Professional services fees	4,300	3,829	7,970	7,348
Total revenues	10,851	9,688	20,817	19,110
Operating expenses	10,944	11,402	22,306	22,690
Income (loss) from operations	(93)	(1,714)	(1,489)	(3,580)
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	10,851	9,688	20,817	19,110
Uniface [Member]
Segment Reporting Information [Line Items]
Software license fees	2,790	2,375	4,771	4,413
Maintenance and subscription fees	8,019	7,309	15,757	14,331
Professional services fees	1,072	1,056	2,278	2,036
Total revenues	11,881	10,740	22,806	20,780
Operating expenses	5,151	4,612	10,551	9,299
Income (loss) from operations	6,730	6,128	12,255	11,481
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	11,881	10,740	22,806	20,780
Professional Services [Member]
Segment Reporting Information [Line Items]
Software license fees	0	0	0	0
Maintenance and subscription fees	0	0	0	0
Professional services fees	39,528	34,405	79,425	69,259
Total revenues	39,528	34,405	79,425	69,259
Operating expenses	31,662	28,836	63,251	58,640
Income (loss) from operations	7,866	5,569	16,174	10,619
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	39,528	34,405	79,425	69,259
Application Services [Member]
Segment Reporting Information [Line Items]
Software license fees	0	0	0	0
Maintenance and subscription fees	0	0	0	0
Professional services fees	17,548	12,162	33,715	23,401
Total revenues	17,548	12,162	33,715	23,401
Operating expenses	19,835	10,963	36,669	21,440
Income (loss) from operations	(2,287)	1,199	(2,954)	1,961
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	17,548	12,162	33,715	23,401
Unallocated Expense [Member]
Segment Reporting Information [Line Items]
Software license fees	0	0	0	0
Maintenance and subscription fees	0	0	0	0
Professional services fees	0	0	0	0
Total revenues	0	0	0	0
Operating expenses	50,883	48,493	102,540	95,788
Income (loss) from operations	(50,883)	(48,493)	(102,540)	(95,788)
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	0	0	0	0
United States [Member]
Segment Reporting Information [Line Items]
Total revenues	171,097	145,740	320,336	277,896
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	171,097	145,740	320,336	277,896
Long-lived assets	948,363		948,363		944,506
Europe and Africa [Member]
Segment Reporting Information [Line Items]
Total revenues	55,726	53,073	110,330	101,411
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	55,726	53,073	110,330	101,411
Long-lived assets	250,075		250,075		33,037
Other interenational operations [Member]
Segment Reporting Information [Line Items]
Total revenues	33,873	27,056	60,004	53,047
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	33,873	27,056	60,004	53,047
Long-lived assets	$ 9,194		$ 9,194		$ 7,838

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