Stock-based Compensation (Total Stock-based Compensation Expense) (Details) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Stock-based compensation expense before taxes	$ 5,319	$ 4,656	$ 10,466	$ 9,160
Related income tax benefits	(1,333)	(1,008)	(2,504)	(1,960)
Stock-based compensation expense, net of taxes	3,986	3,648	7,962	7,200
Basic earnings per share	$ (0.04)	$ (0.04)	$ (0.09)	$ (0.08)
Diluted earnings per share	$ (0.04)	$ (0.04)	$ (0.08)	$ (0.08)
Software Licenses [Member]
Stock-based compensation expense before taxes	37	33	73	65
Maintenance and Service [Member]
Stock-based compensation expense before taxes	461	367	921	732
Selling, General and Administrative [Member]
Stock-based compensation expense before taxes	2,995	2,929	5,951	5,697
Research and Development [Member]
Stock-based compensation expense before taxes	$ 1,826	$ 1,327	$ 3,521	$ 2,666

Reduction in Basic Earnings per Share Impact of Stock Based Compensation

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- Definition

Reduction in Diluted Earnings per Share Impact of Stock Based Compensation

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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