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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Subsequent Events (Details)	1 Months Ended			9 Months Ended
Subsequent Events (Details)	Nov. 30, 2018 USD ($) vessel	Sep. 30, 2018 USD ($)	Jul. 31, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Subsequent Event [Line Items]
Proceeds from financing related to sales and leaseback of vessels (note 8)				$ 156,644,000	$ 153,000,000
Total principal		$ 814,709,000		814,709,000		$ 963,247,000
Remaining Revolving Credit Facilities Maturing in 4Q 2018 \| Revolving Credit Facility
Subsequent Event [Line Items]
Total principal		47,600,000		$ 47,600,000
Aframax Tankers Sale Leaseback
Subsequent Event [Line Items]
Proceeds from financing related to sales and leaseback of vessels (note 8)		$ 156,600,000
Suezmax Tanker Sale Leaseback
Subsequent Event [Line Items]
Proceeds from financing related to sales and leaseback of vessels (note 8)			$ 153,000,000
Subsequent Event \| Working Capital Borrowing Base
Subsequent Event [Line Items]
Revolving credit facilities borrowing capacity	$ 40,000,000
Increase in liquidity	20,000,000
Subsequent Event \| November 2018 Sale-leaseback Transaction
Subsequent Event [Line Items]
Proceeds from financing related to sales and leaseback of vessels (note 8)	$ 84,700,000
Number of vessels \| vessel	4
Subsequent Event \| Minimum \| November 2018 Sale-leaseback Transaction
Subsequent Event [Line Items]
Sale-leaseback, term of contract	10 years
Fixed time charter rate	$ 5,000
Subsequent Event \| Maximum \| November 2018 Sale-leaseback Transaction
Subsequent Event [Line Items]
Sale-leaseback, term of contract	12 years
Fixed time charter rate	$ 7,800
Aframax Tanker \| Teekay Tankers \| Subsequent Event \| Aframax Tankers Sale Leaseback
Subsequent Event [Line Items]
Number of vessels \| vessel	2
Suezmax Tankers \| Teekay Tankers \| Subsequent Event \| Suezmax Tanker Sale Leaseback
Subsequent Event [Line Items]
Number of vessels \| vessel	1
LR2 Tankers \| Teekay Tankers \| Subsequent Event \| LR2 Product Tanker Sale Leaseback
Subsequent Event [Line Items]
Number of vessels \| vessel	1