Derivative Instruments - Schedule of Derivative Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Current portion of derivative assets (note 13)	$ 577	$ 2,905
Current portion of derivative liabilities	(86)	(57)
Reported Value Measurement
Derivative [Line Items]
Current portion of derivative assets (note 13)	577	2,905
Derivative assets	82	2,973
Accrued assets (liabilities)	(230)	(419)
Current portion of derivative liabilities	(86)	(57)
Reported Value Measurement \| Interest rate swap agreements
Derivative [Line Items]
Current portion of derivative assets (note 13)	577	2,905
Derivative assets	82	2,973
Accrued assets (liabilities)	(230)	(422)
Current portion of derivative liabilities	0	0
Reported Value Measurement \| Forward freight agreements
Derivative [Line Items]
Current portion of derivative assets (note 13)	0
Derivative assets	0
Accrued assets (liabilities)	0	(3)
Current portion of derivative liabilities	$ (86)	$ (57)

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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