Gain (loss) recorded in income (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Summary of Derivative Instruments [Abstract]
Increase (Decrease) in Fair Value of Hedged Item in Interest Rate Fair Value Hedge	$ (12)	$ 0
Types of Items Hedged by Interest Rate Derivatives	$12	$—
Derivatives, Gain (Loss) on Derivative, Net	$ 0	$ 0

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of unrealized gain (loss) included in earnings related to the fair value of the hedged item in an interest rate fair value hedge, offset by the gain (loss) on the hedging instrument to the extent that the fair value hedge is determined to be effective.

+ References

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Description of the instruments designated as hedged items in hedges involving interest rate derivatives.

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