Supplemental Statement of Cash Flows Information 2 (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Supplemental Cash Flow Information [Abstract]
Interest payments, net	$ 65us-gaap_InterestPaid	$ 56us-gaap_InterestPaid
Income taxes paid, net	238us-gaap_IncomeTaxesPaidNet	353us-gaap_IncomeTaxesPaidNet
Excess tax benefits from share-based incentive awards included in financing activities from continuing operations	3	4
Share-based incentive awards, Non-cash financing activities	43us-gaap_ShareBasedCompensation	47us-gaap_ShareBasedCompensation
Withholding taxes on share-based incentive awards, Non-cash financing activities	27	28
Discretionary stock contributions to CA, Inc. Savings Harvest Plan, Non-cash financing activities	26	28
Treasury common shares issued in connection with Employee Stock Purchase Plan, Non-cash financing activities	$ 5	$ 4

Discretionary stock contributions noncash financing activities.

No definition available.

Name:	ca_DiscretionaryStockContributionsNoncashFinancingActivities
Namespace Prefix:	ca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Treasury common shares issued in connection with the Company's Employee Stock Purchase Plan included in non-cash financing activities.

+ References

No definition available.

+ Details

Name:	ca_TreasuryCommonSharesIssuedUnderEmployeeStockPurchasePlan
Namespace Prefix:	ca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Withholding taxes on share based incentive awards.

+ References

No definition available.

+ Details

Name:	ca_WithholdingTaxesOnShareBasedIncentiveAwards
Namespace Prefix:	ca_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 20

-Section 55

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=32706628&loc=d3e11374-113907

+ Details

Name:	us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

+ Details

Name:	us-gaap_IncomeTaxesPaidNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of cash paid for interest during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

Name:	us-gaap_InterestPaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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 Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

Name:	us-gaap_ShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_SupplementalCashFlowInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration