Supplemental Cash Flow Information - Changes in Non-cash Working Capital Items Related to Operating Activities (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Accounts receivable and interest receivable	$ (2,128)	$ (13,506)	$ (8,464)
Pool receivable from affiliates	(38,137)	27,481	24,489
Due from affiliates	25,501	12,361	(14,511)
Prepaid expenses and other current assets	8,251	(11,400)	987
Accounts payable and accrued liabilities	(21,265)	32,876	(3,174)
Due to affiliates	(5,718)	(12,181)	(928)
Deferred revenue	1,718	2,039	(2,324)
Other	0	(8,588)	1,999
Change in operating assets and liabilities	$ 44,496	$ (25,880)	$ (50,904)

The increase (decrease) during the reporting period in receivables to be collected from an entity that is controlling, under the control of, or within the same control group as the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

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- Definition

The increase (decrease) during the reporting period in the total amount of receivables from all parties and other operating assets not separately disclosed in the statement of cash flows.

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No definition available.

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- Definition

The increase (decrease) during the reporting period in the amount due to the reporting entity for good and services provided to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The increase (decrease) during the reporting period, excluding the portion taken into income, in the liability reflecting revenue yet to be earned for which cash or other forms of consideration was received or recorded as a receivable.

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The increase (decrease) in obligations owed to an entity that is controlling, under the control of, or within the same control group as the reporting entity by means of direct or indirect ownership.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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The increase (decrease) during the reporting period in other assets used in operating activities less other operating liabilities used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets and liabilities, other noncurrent assets and liabilities, or a combination of other current and noncurrent assets and liabilities.

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The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes.

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No definition available.

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