Additional Cash Flow Information - Net Changes in Working Capital (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Accounts receivable	$ 398	$ 2,331
Prepaid expenses and other current assets	(350)	(396)
Accounts payable	2,048	4,494
Accounts payable due to related parties	(910)	2,300
Accrued liabilities	14,439	6,375
Other, net	(746)	(1,617)
Net changes in working capital	$ 14,879	$ 13,487

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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=123570139&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in the obligations due for goods and services provided by 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 entities' management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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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

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid.

+ References

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- Definition

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

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- Definition

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

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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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