Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Accounting Policies (Textuals) [Abstract]
Percentage of cash and cash equivalents held by the company's foreign subsidiaries outside the United States	54.00%
Interest payments	$ 25	$ 35
Income and other taxes paid, net	198	87
Share based incentive awards	51	61
Withholding taxes on share based incentive awards	25	25
Discretionary stock contributions to CA, Inc. Savings Harvest Plan	13	25
Notional Pooling Arrangement [Member]
Line of Credit Facility [Line Items]
Line of credit facility, amount outstanding	68
Proceeds from lines of credit	154
Repayments of lines of credit	$ 86

Accounting policies.

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Discretionary Stock Contributions.

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Income and other taxes paid, net.

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Percentage of Cash and Cash Equivalents maintained outside of the United States: At the balance sheet date, the percentage of cash and cash equivalents held by the Company's foreign subsidiaries.

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Withholding taxes on share based incentive awards.

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- Definition

The amount of cash paid for interest during the period.

+ References

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Amount borrowed under the credit facility as of the balance sheet date.

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-Name Regulation S-X (SX)
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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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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

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The cash outflow to pay off an obligation from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity.

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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.

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-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.

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