The amount of expense charged against earnings by an Entity to record deferred gains and losses on hedge instruments. Examples include gain on economic hedges, amortization of gain on designated fair value hedge and so forth.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt premium.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Short-Term Borrowings and Long-Term Debt Other Debt Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2014	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2016	Mar. 31, 2014
Debt Instrument [Line Items]
Short-term Debt								$ 500,000
2.7% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 250,000
Debt Instrument, Interest Rate, Stated Percentage		2.70%
Debt Instrument, Unamortized Discount		$ 553
Debt Instrument, Basis Spread on Variable Rate		0.20%
3.95% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 250,000
Debt Instrument, Interest Rate, Stated Percentage		3.95%
Debt Instrument, Unamortized Discount		$ 458
Debt Instrument, Basis Spread on Variable Rate		0.25%
4.75% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 450,000
Debt Instrument, Unamortized Discount						$ 207
Debt Instrument, Basis Spread on Variable Rate						0.45%
5.625% Senior Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 150,000							$ 400,000
Debt Instrument, Interest Rate, Stated Percentage									5.625%
Debt Instrument, Unamortized Discount									$ 6,260
Debt Instrument, Basis Spread on Variable Rate							0.30%
Debt Instrument, Unamortized Premium		$ 9,779
6.375% Junior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 250,000
Debt Instrument, Interest Rate, Stated Percentage						6.375%
5.45% Junior Subordinated Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount								$ 500,000
Debt Instrument, Interest Rate, Stated Percentage								5.50%
Fair Value Hedging [Member] \| 2.7% Senior Notes [Member]
Debt Instrument [Line Items]
Derivative, Gain on Derivative	$ 6,500
Amortization of Deferred Hedge Gains			$ 1,804	$ 1,804	$ 1,804