Derivative Instruments and Hedging Activities - Components of Fair Value of Derivative Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015
Derivative Assets, Fair Value
Derivative assets	$ 2,691	$ 282
Gross amounts offset in the balance sheet	(2,691)	(282)
Total derivative assets - net	0	0
Derivative Liabilities, Fair Value
Derivative liabilities	(26,206)	(73,269)
Gross amounts offset in the balance sheet	2,691	282
Cash collateral pledged	0	3,160
Total derivative liabilities - net	(23,515)	(69,827)
Not Designated as Hedging Instrument \| Propane Contracts
Derivative Assets, Fair Value
Derivative assets	2,691	282
Derivative Liabilities, Fair Value
Derivative liabilities	$ (26,206)	$ (73,269)

Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of asset associated with financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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