Face (par) amount of debt instrument at time of issuance.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

+ References

No definition available.

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- Definition

Description of debt redemption features under terms of the debt agreement.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

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Indebtedness (Senior Notes Narrative) (Details) - Senior notes, net [Member] - USD ($) $ in Millions			6 Months Ended
	Sep. 14, 2015	Aug. 11, 2015	Sep. 30, 2015
2.375% senior notes due February 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage		100.00%
3.05% senior notes due August 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 400
Debt instrument, interest rate, stated percentage		3.05%
Debt instrument, interest rate, effective percentage		3.092%
Debt instrument, interest payment dates			February 1 and August 1
Debt instrument, redemption, description			The Company has the option to redeem the 2020 Notes prior to their maturity, in whole or in part, either at 100% of the principal amount of the notes plus any accrued but unpaid interest or at the applicable make-whole premium
2.95% senior notes due June 2016 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 250
Debt instrument, interest rate, stated percentage			2.95%
3.25% senior notes due October 2015 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 250
Debt instrument, interest rate, stated percentage	3.25%
Debt instrument, redemption price, percentage of principal redeemed	100.00%