Indebtedness (Money Market Loans Narrative) (Details) - Money market loans [Member] - Agreement expiring in July 2016 [Member] - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2015	Jul. 31, 2015
Debt Instrument [Line Items]
Short-term debt, terms	advances are generally overnight or for up to seven days. The amount, term and interest rate of an advance are established through mutual agreement with the financial institution when the Company requests such an advance
Maximum [Member]
Debt Instrument [Line Items]
Short term debt maturity period	7 days
Subsequent Event [Member]
Debt Instrument [Line Items]
Short-term debt, maximum borrowing amount		$ 35

Maximum borrowing amount of short-term advances without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the arrangement.

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

+ 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 210.5-02.19(b))

-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 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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