Business Combination Contingent Cash Consideration Payable

No definition available.

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- Definition

Number of customers acquired through acquisition

+ References

No definition available.

+ Details

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

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- Definition

The amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and were recognized by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

+ Details

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

+ Details

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Balance Type:	debit
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- Definition

Amount of long-term debt due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Details

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- Details

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- Details

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- Details

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Acquisitions - Additional Information (Detail)		3 Months Ended								12 Months Ended
Acquisitions - Additional Information (Detail)	Apr. 01, 2015 USD ($) shares	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares \| shares	592,970
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned		$ 0				$ 0				$ 0	$ 0	$ 30,164,000
Cash paid for acquisition										11,945,000	0	20,930,000
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed												514,000	$ 786,000
Revenues		180,403,000	$ 126,936,000	$ 125,084,000	$ 185,160,000	141,874,000	$ 108,348,000	$ 102,342,000	$ 146,296,000	617,583,000	498,860,000	459,244,000
Net Income		26,101,000	$ 6,833,000	$ 6,046,000	$ 19,144,000	$ 11,863,000	$ 4,416,000	$ 8,029,000	$ 20,367,000	58,124,000	44,675,000	41,140,000
ARM Energy [Member]
Business Combination, Liabilities Arising from Contingencies, Amount Recognized		$ 2,500,000.0								$ 2,500,000.0
Chipola [Member]
Number of customers acquired through acquisition										800
Central Gas [Member]
Number of customers acquired through acquisition										325
Gatherco [Member]
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 30,200,000											30,164,000
Cash paid for acquisition	27,500,000											27,494,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt	1,696,000											1,696,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	$ 6,800,000											6,806,000
Business Combination Contingent Cash Consideration Payable												15,000,000
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed												1,300,000
Revenues										$ 33,300,000	26,600,000	16,700,000
Net Income										$ 8,913,000	$ 2,100,000	$ 312,000