Segment Reporting - Capital Expenditures

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Revenue from transporting cargo and freight between locations.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Gain (loss) incurred in hedging activities.

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

Revenue from the sale of oil and gas during the period.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

+ References

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- Definition

Revenue from sale of oil and gas purchased from other sources.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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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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No definition available.

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Segment Information Industry Segment Results (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	$ 405,623	$ 317,763
Purchased Gas Revenue	18,055	8,979
Midstream Revenue	26,254
(Loss) Gain on Commodity Derivative Instruments	35,087	(22,463)
Other Operating Income	10,710	15,650
Total Revenue and Other Operating Income	495,729	319,929
Earnings (Loss) From Continuing Operations Before Income Tax	759,240	(138,429)
Segment Assets	8,122,229	9,019,597	$ 6,931,913
Depreciation, Depletion and Amortization	124,667	95,678
Capital Expenditures	232,485	103,922
Revenues	495,729	319,929
Equity in Earnings	1,778	12,330	48,346
Investments in unconsolidated equity affiliates			$ 175,371	$ 169,208
Operating Segments [Member]
Segment Reporting Information [Line Items]
Equity in Earnings	1,778	12,330
Investments in unconsolidated equity affiliates	20,678	197,385
NJR Energy Services Company [Member]
Segment Reporting Information [Line Items]
Revenues	72,637	57,030
Direct Energy Business Marketing LLC [Member]
Segment Reporting Information [Line Items]
Revenues	57,907	46,366
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	0
Purchased Gas Revenue	0
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	0
Other Operating Income	0
Total Revenue and Other Operating Income	0
Earnings (Loss) From Continuing Operations Before Income Tax	623,897
Segment Assets	102,668
Depreciation, Depletion and Amortization	0
Capital Expenditures	0
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	0
Purchased Gas Revenue	0
Midstream Revenue	(37,924)
(Loss) Gain on Commodity Derivative Instruments	0
Other Operating Income	(81)
Total Revenue and Other Operating Income	(38,005)
Earnings (Loss) From Continuing Operations Before Income Tax	0
Segment Assets	(14,770)	0
Depreciation, Depletion and Amortization	0
Capital Expenditures	0
Operating Segments [Member]
Segment Reporting Information [Line Items]
Earnings (Loss) From Continuing Operations Before Income Tax	135,343	(135,176)
Operating Segments [Member] \| Other Gas [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	12,784	16,294
Purchased Gas Revenue	18,055	8,979
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	51,504	22,088
Other Operating Income	10,791	15,650
Total Revenue and Other Operating Income	93,134	63,011
Earnings (Loss) From Continuing Operations Before Income Tax	(13,657)	(186,560)
Operating Segments [Member] \| Coalbed Methane [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	57,501	58,626
Purchased Gas Revenue	0	0
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	(2,430)	(9,198)
Other Operating Income	0	0
Total Revenue and Other Operating Income	55,071	49,428
Earnings (Loss) From Continuing Operations Before Income Tax	13,117	3,608
Operating Segments [Member] \| Utica Shale [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	130,322	53,668
Purchased Gas Revenue	0	0
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	(4,474)	(2,688)
Other Operating Income	0	0
Total Revenue and Other Operating Income	125,848	50,980
Earnings (Loss) From Continuing Operations Before Income Tax	56,107	17,807
Operating Segments [Member] \| Marcellus Shale [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	205,016	189,175
Purchased Gas Revenue	0	0
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	(9,513)	(32,665)
Other Operating Income	0	0
Total Revenue and Other Operating Income	195,503	156,510
Earnings (Loss) From Continuing Operations Before Income Tax	44,242	29,969
E&P [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	405,623	317,763
Purchased Gas Revenue	18,055	8,979
Midstream Revenue	0
(Loss) Gain on Commodity Derivative Instruments	35,087	(22,463)
Other Operating Income	10,791	15,650
Total Revenue and Other Operating Income	469,556	319,929
Earnings (Loss) From Continuing Operations Before Income Tax	99,809	(135,176)
Segment Assets	6,034,660	6,350,772
Depreciation, Depletion and Amortization	115,866	95,678
Capital Expenditures	216,508	103,922
CNXM [Member] \| Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue		0
Purchased Gas Revenue		0
(Loss) Gain on Commodity Derivative Instruments		0
Other Operating Income		0
Total Revenue and Other Operating Income		0
Earnings (Loss) From Continuing Operations Before Income Tax		(3,253)
Segment Assets		2,668,825
Depreciation, Depletion and Amortization		0
Capital Expenditures		0
CNXM [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Natural Gas, NGLs and Oil Revenue	0
Purchased Gas Revenue	0
Midstream Revenue	64,178
(Loss) Gain on Commodity Derivative Instruments	0
Other Operating Income	0
Total Revenue and Other Operating Income	64,178
Earnings (Loss) From Continuing Operations Before Income Tax	35,534	0
Segment Assets	1,999,671	$ 0
Depreciation, Depletion and Amortization	8,801
Capital Expenditures	$ 15,977