Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
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Amount, before tax, of increase (decrease) in the cumulative translation adjustment from gain (loss) on foreign currency derivatives that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Hedging Activities - Narrative (Details) $ in Millions	3 Months Ended
Hedging Activities - Narrative (Details) $ in Millions	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 EUR (€)	Jun. 30, 2018 GBP (£)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 GBP (£)	Mar. 31, 2018 USD ($)	Jun. 30, 2017 EUR (€)
Derivative [Line Items]
Long-term debt outstanding					$ 7,719		$ 7,880
Derivatives used in Net investment hedge, gains (loss) gross	$ 161	$ (114)
Gains (losses) from cash flow hedges	0	14
Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Gains (losses) from cash flow hedges		$ (14)
Foreign Exchange Contract \| Derivatives not Designated for Hedge Accounting
Derivative [Line Items]
Notional values of financial instruments					39		29
Cross Currency Swap \| Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Notional values of financial instruments					3,412		3,412
Forward Contracts \| Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Notional values of financial instruments					$ 162		$ 162
Net Investment Hedging \| Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Derivatives used in Net investment hedge, gains (loss) gross	$ 34
Net Investment Hedging \| Cross Currency Swap [Member] \| Derivatives Designated for Hedge Accounting
Derivative [Line Items]
Notional values of financial instruments \| £						£ 432,000,000
Euro Denominated Notes \| Term Loan
Derivative [Line Items]
Long-term debt outstanding \| €			€ 1,950,000,000.00					€ 1,200,000,000.00
British Pound Sterling Denominated Notes \| Term Loan
Derivative [Line Items]
Long-term debt outstanding \| £				£ 450,000,000