Effects of Economic Hedging Related to Natural Gas Inventory, Tax

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- Definition

Increase (Decrease) in Economic Hedging Related to Natural Gas Inventory, Before Taxes

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No definition available.

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- Definition

Net Financial Earnings (Loss) is a non-GAAP measure of earnings that eliminates certain timing differences surrounding the recognition of certain gains or losses associated with derivative activity

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No definition available.

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Net Financial Earnings (Loss), Reconciling Items [Abstract]

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- Definition

Unrealized Gain (Loss) on Derivatives and Commodity Contracts, Tax

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No definition available.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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BUSINESS SEGMENT AND OTHER OPERATIONS DATA - NET FINANCIAL EARNINGS LOSS RECONCILIATION (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting [Abstract]
Consolidated net financial earnings									$ 240,486	$ 149,392	$ 138,085
Less:
Unrealized loss (gain) on derivative instruments and related transactions									26,770	(11,241)	46,883
Unrealized loss (gain) on derivative instruments and related transactions, tax effect									(4,512)	4,062	(17,018)
Effects of economic hedging related to natural gas inventory									(22,570)	38,470	(36,816)
Effects of economic hedging related to natural gas inventory, tax effect									7,362	(13,964)	13,364
NET INCOME	$ (16,255)	$ (14,274)	$ 140,266	$ 123,699	$ (36,523)	$ 18,957	$ 114,702	$ 34,929	$ 233,436	$ 132,065	$ 131,672