Segment Reporting (Details) (USD $) In Millions	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Revenue:
License	$ 189.5	$ 171.2
Maintenance	264.6	253.8
Professional services	48.3	35.9
Total revenue	502.4	460.9
Direct and allocated indirect segment operating expenses	331.9	304.1
Segment operating income	170.5	156.8
Unallocated operating expenses	(55.4)	(48.7)
Other loss, net	(1.6)	(5.5)
Earnings before income taxes	113.5	102.6
Enterprise Service Management [Member]
Revenue:
License	118.5	113.2
Maintenance	141.2	137.1
Professional services	48.3	35.9
Total revenue	308.0	286.2
Direct and allocated indirect segment operating expenses	248.6	220.7
Segment operating income	59.4	65.5
Mainframe Service Management [Member]
Revenue:
License	71.0	58.0
Maintenance	123.4	116.7
Total revenue	194.4	174.7
Direct and allocated indirect segment operating expenses	83.3	83.4
Segment operating income	$ 111.1	$ 91.3

Direct segment operating expenses includes expenses that are directly allocated to particular segments and are controllable by segment management.

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- Definition

The sum of total indirect expenses that primarily includes operating expenses not specifically identified to a particular segment or controllable by segment management.

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- Definition

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

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- Definition

Revenue derived from maintenance services provided under contracts or arrangements with clients. For example, it may include the maintenance of software, plant and equipment, and facilities.

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- Definition

The aggregate amount of income (expense) from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Article 5

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Article 5

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- Definition

Amount of income or loss for the reportable segment before income taxes and extraordinary items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27

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Amount of income or loss for the reportable segment before unusual Items, equity method income or loss, income taxes, and extraordinary items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27

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- Definition

Revenue from providing technology services. The services may include training, installation, engineering or consulting. Consulting services often include implementation support, software design or development, or the customization or modification of the licensed software.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 97-2
-Paragraph 63

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