Commitments and Contingencies - Additional Information (Detail) - Natural Gas Purchasing and Natural Gas Processing Contract [Member] $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($) MMBTU $ / MMBTU
Loss Contingencies [Line Items]
Pipeline fee paid \| $ / MMBTU	0.45
Holding pipeline capacity \| MMBTU	10,000
Purchasing and processing contract expiry date	Jun. 01, 2021
Company's share of remaining commitment amount \| $	$ 3.9

Oil and gas delivery commitments and contracts remaining commitment amount.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The delivery price committed to in the contract.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
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Period Type:	instant

- Definition

Significant oil and gas supplies dedicated or contracted to the enterprise that can be used to fulfill existing contracts or agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1207
-Paragraph (b)
-Subparagraph (2)(ii)

+ Details

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- Details

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