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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

+ References

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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

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher SEC
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Fair Value of Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Assets:
Investments	$ 3,644		$ 3,678
Energy Marketing Contracts Assets, Current	153		1,055
Quoted Prices in Active Markets (Level 1) \| Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	0		0
Significant Other Observable Inputs (Level 2) \| Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	433		1,018
Equity Securities [Member]
Assets:
Investments	18		0
Equity Securities [Member] \| Quoted Prices in Active Markets (Level 1)
Assets:
Investments		$ 18
Guaranteed Income Fund [Member] \| Quoted Prices in Active Markets (Level 1)
Assets:
Investments	0		0
Guaranteed Income Fund [Member] \| Significant Other Observable Inputs (Level 2)
Assets:
Investments	0
Guaranteed Income Fund [Member] \| Significant Unobservable Inputs (Level 3)
Assets:
Investments	279		287
Investments - other \| Quoted Prices in Active Markets (Level 1)
Assets:
Investments	3,347		3,391
Investments - other \| Significant Other Observable Inputs (Level 2)
Assets:
Investments	0		0
Investments - other \| Significant Unobservable Inputs (Level 3)
Assets:
Investments	0
Mark-to-market energy assets, including put option \| Quoted Prices in Active Markets (Level 1)
Assets:
Mark-to-market energy assets, including put option	0		0
Mark-to-market energy assets, including put option \| Significant Other Observable Inputs (Level 2)
Assets:
Mark-to-market energy assets, including put option	153
Energy Marketing Contracts Assets, Current			1,055
Fair Value \| Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	433		1,018
Fair Value \| Equity Securities [Member]
Assets:
Investments		$ 18
Fair Value \| Guaranteed Income Fund [Member]
Assets:
Investments	279		287
Fair Value \| Investments - other
Assets:
Investments	3,347		3,391
Fair Value \| Mark-to-market energy assets, including put option
Assets:
Mark-to-market energy assets, including put option	$ 153		$ 1,055