Accounts Payable Subject To Master Netting Arrangement

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- Definition

Cash Paid On Derivative Settlement

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- Definition

Cash Received On Derivative Settlement

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- Definition

Number Of Counterparties With Master Repurchase Agreements

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- Definition

Strike Price Per Gallon For The Propane Swap Agreements

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- Definition

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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- Definition

Nominal volume used to calculate payments on a derivative instrument.

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- Definition

The strike price on the price risk option contract such as a put option or a call option.

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- Definition

Current liabilities attributable to energy marketing activities (trading activities). Current energy marketing (trading activities) are when entities engage in both financial and physical trading to increase profits, manage their commodity price risk and enhance system reliability. They may trade electricity, coal, natural gas and oil. These entities typically use a variety of financial instruments, including forward contracts, options and swaps.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount as of the balance sheet date of the asset arising from energy trading activities that involves the purchase and sale of energy under forward contracts at fixed and variable prices and the buying and selling of financial energy contracts that include exchange futures and options and over the counter options and swaps, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash outflow for derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3505-108585

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Derivative Instruments - Additional Information (Detail) $ in Thousands, gal in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2016 USD ($) Counterparty $ / gal	Sep. 30, 2016 USD ($) Counterparty $ / gal gal	Dec. 31, 2015 USD ($) Counterparty $ / gal gal
Derivative [Line Items]
Energy Marketing Contracts Assets, Current	$ 477	$ 477	$ 153
Energy Marketing Contract Liabilities, Current	29	$ 29	$ 433
Propane Swap Agreement [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| gal		4.1	2.5
Cash Paid On Derivative Settlement	484
Put Option [Member]
Derivative [Line Items]
Payments for Derivative Instrument, Financing Activities			$ 143
Cash Received On Derivative Settlement	$ 239
Forward Contracts [Member]
Derivative [Line Items]
Number Of Counterparties With Master Repurchase Agreements \| Counterparty	2	2	2
Accounts Payable Subject To Master Netting Arrangement			$ 431
Mark To Market Energy Assets [Member] \| Propane [Member]
Derivative [Line Items]
Energy Marketing Contracts Assets, Current	$ 237	$ 237
Mark To Market Energy Assets [Member] \| Future [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| gal		6.0
Mark To Market Energy Liabilities [Member] \| Future [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| gal		1.8
Strike Price 4 [Member] \| Propane Swap Agreement [Member]
Derivative [Line Items]
Strike Price Per Gallon For The Propane Swap Agreements \| $ / gal	0.5250	0.5250	0.5200
Strike Price 2 [Member] \| Propane Swap Agreement [Member]
Derivative [Line Items]
Strike Price Per Gallon For The Propane Swap Agreements \| $ / gal	0.5525	0.5525	0.5950
Put Option Strike Price 1 [Member] \| Put Option [Member]
Derivative [Line Items]
Derivative, Price Risk Option Strike Price \| $ / gal			0.4950
Put Option Strike Price 2 [Member] \| Put Option [Member]
Derivative [Line Items]
Derivative, Price Risk Option Strike Price \| $ / gal			0.4888
Put Option Strike Price 3 [Member] \| Put Option [Member]
Derivative [Line Items]
Derivative, Price Risk Option Strike Price \| $ / gal			0.4500
Put Option Strike Price 4 [Member] \| Put Option [Member]
Derivative [Line Items]
Derivative, Price Risk Option Strike Price \| $ / gal			0.4200