Related Party Transactions - Summary of Related Party Transactions (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
RSA pool management fees and commissions	$ (2,799)	$ (9,813)	$ (10,445)
Commercial management fees	(1,187)	(1,870)	(1,236)
Vessel operating expenses	(175,389)	(182,598)	(137,164)
Strategic and administrative service fees	(21,185)	(10,122)	(8,356)
Entities Under Common Control
Related Party Transaction [Line Items]
RSA pool management fees and commissions	2,799	9,813	10,445
Commercial management fees	1,187	1,870	1,236
Strategic and administrative service fees	(7,026)	(15,508)	(14,701)
Time-charter
Related Party Transaction [Line Items]
Revenues	0	5,404	392
Time-charter \| Entities Under Common Control
Related Party Transaction [Line Items]
Revenues	0	0	4,558
Technical management fee
Related Party Transaction [Line Items]
Vessel operating expenses	(8,775)	(9,155)	(7,039)
Technical management fee \| Entities Under Common Control
Related Party Transaction [Line Items]
Revenues	4,890	11,742	10,413
Vessel operating expenses	0	0	(430)
Secondment fees
Related Party Transaction [Line Items]
Strategic and administrative service fees	(382)	0	0
Secondment fees \| Entities Under Common Control
Related Party Transaction [Line Items]
Strategic and administrative service fees	(248)	(644)	(675)
Lay-up Services
Related Party Transaction [Line Items]
Revenues	33	302	0
LNG terminal services
Related Party Transaction [Line Items]
Revenues	388	70	0
Technical management fee revenue
Related Party Transaction [Line Items]
Revenues	7,666	0	0
Service revenue
Related Party Transaction [Line Items]
Revenues	1,939	0	0
Service revenue \| Entities Under Common Control
Related Party Transaction [Line Items]
Revenues	$ 1,772	$ 5,482	$ 4,023

Commercial Management Fees Related Party

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- Definition

Pool Management Fees And Commissions Related Party

+ References

No definition available.

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- Definition

The aggregate direct operating costs incurred during the reporting period.

+ References

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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.

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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ 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(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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