Accounting For Share-Based Compensation 2 (Details) (USD $)	3 Months Ended	6 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Share Based Compensation Arrangement By Share Based Payment Award (Textual) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			600,000	1,200,000
Company's common stock purchase price as a percentage of of the closing price of the stock on the last day of the plan period			95.00%
Stock purchase plan, maximum number of shares	30,000,000		30,000,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0		700,000	500,000
Shares of Restricted Stock Awards and Restricted Stock Units Granted During Period		Less than 0.1 million
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0	$ 18.08	$ 24.08	$ 21.23
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		100,000	3,600,000	4,700,000
Shares of Restricted Stock Awards and Restricted Stock Units Granted During Period	Less than 0.1 million
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 22.47	$ 18.66	$ 24.65	$ 21.39

Share Based Compensation Arrangement By Share Based Payment Award Textual

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- Definition

Shares of restricted stock awards and restricted stock units granted during period.

+ Details

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Namespace Prefix:	ca
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Period Type:	duration

- Definition

Stock purchase plan maximum number of shares.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Shares of the Company's stock could be purchased at this percentage of the closing price of the stock on the last day of the plan period.

+ Details

Name:	ca_StockPurchasePlanPurchasePriceStatedAsPercentage
Namespace Prefix:	ca
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Gross number of share options (or share units) granted during the period.

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Data Type:	xbrli:sharesItemType
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