Non-Derivatives Used in Net Investment Hedge, Increase (Decrease), Gross of Tax

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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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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No definition available.

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Nominal or face amount used to calculate payment on derivative.

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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.

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- Definition

Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge.

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- Definition

The cash inflow provided by derivative instruments during the period, which are classified as investing activities, excluding those designated as hedging instruments.

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- Definition

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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Hedging Activities - Narrative (Details) £ in Millions, $ in Billions	3 Months Ended		6 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 EUR (€)	Sep. 30, 2020 CAD ($)	Sep. 30, 2020 GBP (£)	Apr. 27, 2020 USD ($)	Apr. 27, 2020 EUR (€)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 CAD ($)	Sep. 30, 2019 EUR (€)	Sep. 30, 2019 GBP (£)	Jun. 30, 2019 GBP (£)
Derivative [Line Items]
Gains on non-derivative net investment hedge		$ 20,000,000		$ 30,000,000
Gains (losses) from cash flow hedges recorded within other comprehensive income	$ (19,000,000)	13,000,000	$ (24,000,000)	25,000,000
Derivatives designated for hedge accounting
Derivative [Line Items]
Gain (loss) from net investment hedges recorded within other comprehensive income	(83,000,000)	91,000,000	(117,000,000)	67,000,000
Forward contracts to hedge Euro against British Pound cash flows \| Derivatives not Designated for Hedge Accounting
Derivative [Line Items]
Notional values of financial instruments	44,000,000		44,000,000							$ 29,000,000
Gain (loss) on financial instruments		(20,000,000)		(39,000,000)
Net Investment Hedging \| Derivatives designated for hedge accounting
Derivative [Line Items]
Derivatives used in net investment hedge, gains (loss) gross	(12,000,000)	20,000,000	(63,000,000)	9,000,000
Net Investment Hedging \| November 2018 cross currency swaps \| Derivatives designated for hedge accounting
Derivative [Line Items]
Notional values of financial instruments						$ 1.5						$ 1.5			£ 932
Proceeds from termination of derivative instruments				84,000,000
Gain (loss) on financial instruments				34,000,000
Cash Flow Hedging \| Derivatives designated for hedge accounting
Derivative [Line Items]
Gains (losses) from cash flow hedges recorded within other comprehensive income	(23,000,000)	$ 17,000,000	(28,000,000)	$ 35,000,000
Cash Flow Hedging \| Cross currency swap \| Derivatives designated for hedge accounting
Derivative [Line Items]
Notional values of financial instruments	$ 2,600,000,000		$ 2,600,000,000							$ 2,900,000,000
Cash Flow Hedging \| Forward starting interest rate swaps \| Derivatives designated for hedge accounting
Derivative [Line Items]
Notional values of financial instruments								$ 500,000,000	€ 600,000,000
Euro Denominated Notes \| Term Loan
Derivative [Line Items]
Long-term debt outstanding \| €													€ 1,950,000,000
Euro Denominated Notes \| Term Loan \| Net Investment Hedging
Derivative [Line Items]
Long-term debt outstanding \| €					€ 1,700,000,000						€ 1,700,000,000
British Pound Sterling Denominated Notes \| Term Loan
Derivative [Line Items]
Long-term debt outstanding \| £							£ 450							£ 450