Derivatives (Effect of interest rate contracts on statement of operations) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Effect of Interest rate Contracts [Abstract]
Loss recognized in income on interest rate contracts	$ 824	$ 3,893	$ 8,603
(Gain) recognized in AOCI on interest rate contracts (effective portion)	(633)	(4,445)	(9,916)
Loss reclassified from AOCI into income (effective portion)	789	3,893	8,628
(Gain) loss recognized in income on interest rate contracts (ineffective portion and amount excluded from effectiveness testing)	$ 35		$ (25)

No definition available.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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- Definition

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

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Amount before tax 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).

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