Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ 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=66902209&loc=d3e3213-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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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- Details

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Period Type:

Investment in Unconsolidated Affiliate - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Equity Method Investments [Line Items]
Purchase of LNG Interest from an affiliate		$ 0	$ 361	$ 1,197
Gulf LNG Holdings Group, LLC Acquisition [Member]
Schedule Of Equity Method Investments [Line Items]
Purchase of LNG Interest from an affiliate	$ 72,700
Carrying value of LNG Interest	64,100
Purchase price excess paid over the carrying value	$ 8,600
Long lived assets useful life		28 years