Supplemental Cash Flow Information - Changes in Non-cash Working Capital Items Related to Operating Activities (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Accounts receivable, including other current assets	$ (171,342)	$ (16,020)	$ 14,603
Pool receivables from affiliates	56,549	(40,999)	16,193
Due from affiliates	38,966	9,440	17,562
Increase (Decrease) in Inventories	(28,628)	(15,564)	8,322
Prepaid expenses	119	57	445
Accounts payable and accrued liabilities	83,244	9,778	(13,996)
Due to affiliates	(16,431)	(1,147)	(32,641)
Increase (Decrease) in Deferred Revenue	7,485	(557)	(3,898)
Other	(394)	60	0
Change in operating assets and liabilities	$ (30,432)	$ (54,952)	$ 6,590

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&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

Amount of increase (decrease) in receivables, and operating assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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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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- Definition

Amount of increase (decrease) in deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

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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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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

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Amount of increase (decrease) in operating assets after deduction of operating liabilities classified as other.

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Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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- References

No definition available.

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