Additional Cash Flow Information - Net Changes in Working Capital (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Accounts receivable, net	$ 4	$ (8)
Accounts receivable due from related parties	62	(1,819)
Prepaid expenses and other current assets	297	(86)
Accounts payable and accrued liabilities	7,611	(8,884)
Other, net	(3,871)	(292)
Net changes in components of operating assets and liabilities, net of acquisitions (See Note 13)	$ 4,103	$ (11,089)

Amount of increase (decrease) in obligations incurred but not paid, and operating obligations classified as other.

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=109223946&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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=109223946&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.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

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- References

No definition available.

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