The actual hull coverage ratio of the Company as at period end.

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- Definition

Debt Covenant Free Cash Requirement

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The minimum liquidity required by covenants of certain debt currently held by the company. Liquidity is defined as cash, cash equivalents and undrawn committed revolving credit lines with at least six months to maturity.

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The minimum free liquidity and undrawn revolving credit line required by covenants of certain debt currently held by the Company, as a percentage of total debt.

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No definition available.

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- Definition

The minimum hull coverage ratio as required by certain covenants for debts held by the Company.

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No definition available.

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- Definition

Debt covenants from certain debts held by the Company that is guaranteed by the Company's parent, which requires the Company's parent to maintain a minimum amount of free cash and undrawn committed revolving credit lines, as a percentage of the parent's total consolidated debt.

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No definition available.

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- Definition

Debt Instrument, Collateral, Number of Vessels

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Long-term Debt, Maturities, Revolving Credit Facility, Decrease in Amount Available Remaining Fiscal Year

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No definition available.

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Long-term Debt, Maturities, Revolving Credit Facility, Decrease in Amount Available Year Five

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Long-term Debt, Maturities, Revolving Credit Facility, Decrease in Amount Available Year Four

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Long-term Debt, Maturities, Revolving Credit Facility, Decrease in Amount Available Year Three

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No definition available.

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Long-term Debt, Maturities, Revolving Credit Facility, Decrease in Amount Available Year Two

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No definition available.

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- Definition

Number of debt instruments.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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No definition available.

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Long-Term Debt - Additional Information - Revolvers and Term Loans (Details)	1 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($) credit_facility	Sep. 30, 2018 USD ($) loan credit_facility vessel	Dec. 31, 2017 USD ($)	Jan. 31, 2016 USD ($)
Debt Instrument [Line Items]
Total principal	$ 963,247,000	$ 814,709,000	$ 963,247,000
Secured Debt Two \| Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Debt term		6 months
Maintain the greater of free cash liquidity		$ 100,000,000
Minimum liquidity as a percentage of debt		7.50%
Term Loans
Debt Instrument [Line Items]
Total principal	423,512,000	$ 348,946,000	423,512,000
Remaining Secured Debt \| Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Maintain the greater of free cash liquidity		$ 50,000,000
Minimum liquidity as a percentage of debt		5.00%
Term Loan Due 2021 \| Term Loans
Debt Instrument [Line Items]
Number of debt instruments \| credit_facility		3
Total principal	$ 423,500,000	$ 348,900,000	$ 423,500,000
Debt instrument, interest rate, stated percentage	5.40%	5.40%	5.40%
Maturing in May 2021 \| Term Loans
Debt Instrument [Line Items]
Number of debt instruments \| loan		2
Revolver 2017
Debt Instrument [Line Items]
Number of debt instruments \| credit_facility	2
Debt instrument, face amount	$ 270,000,000.00		$ 270,000,000.00
Repayments of debt	$ 215,800,000
Collateral, number of vessels \| vessel		8
Minimum hull coverage ratios		125.00%
Actual hull coverage ratio	191.00%	174.00%	191.00%
Revolver 2017 \| Not Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Minimum liquidity covenant requirement		$ 35,000,000
Minimum liquidity as a percentage of consolidated debt covenant requirement		5.00%
2016 Debt Facility
Debt Instrument [Line Items]
Debt instrument, face amount				$ 894,400,000.0
Collateral, number of vessels \| vessel		29
Minimum hull coverage ratios		125.00%
Actual hull coverage ratio	145.00%	134.00%	145.00%
2016 Debt Facility \| Not Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Minimum liquidity covenant requirement		$ 35,000,000
Minimum liquidity as a percentage of consolidated debt covenant requirement		5.00%
Remaining Revolving Credit Facilities Maturing in November 2018 \| Revolving Credit Facility
Debt Instrument [Line Items]
Total principal		$ 47,600,000
Remaining Secured Debt \| Term Loans
Debt Instrument [Line Items]
Number of debt instruments \| credit_facility		2
Collateral, number of vessels \| vessel		6
Minimum
Debt Instrument [Line Items]
Percentage of margin		0.30%
Minimum \| Revolver 2017 \| Not Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Debt term		6 months
Minimum \| 2016 Debt Facility \| Not Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Debt term		6 months
Maximum
Debt Instrument [Line Items]
Percentage of margin		2.75%
LIBOR \| Minimum \| Term Loans
Debt Instrument [Line Items]
Percentage of margin		0.30%	0.30%
LIBOR \| Maximum \| Term Loans
Debt Instrument [Line Items]
Percentage of margin		2.00%	2.00%
Revolving Credit Facility
Debt Instrument [Line Items]
Total principal	$ 539,735,000	$ 465,763,000	$ 539,735,000
Revolving Credit Facility \| Revolving Credit Facilities Due through 2022
Debt Instrument [Line Items]
Number of debt instruments \| credit_facility		3
Revolving credit facilities borrowing capacity	628,300,000.0	$ 500,600,000.0	628,300,000.0
Undrawn amount of revolving credit facility	$ 88,600,000	34,800,000	$ 88,600,000
Long-term debt, maturities, revolving credit facility, decrease in amount available remaining fiscal year		51,400,000
Long-term debt, maturities, revolving credit facility, decrease in amount available, year 2		19,200,000
Long-term debt, maturities, revolving credit facility, decrease in amount available, year 3		19,200,000
Long-term debt, maturities, revolving credit facility, decrease in amount available, year 4		311,900,000
Long-term debt, maturities, revolving credit facility, decrease in amount available, year 5		$ 98,900,000
Revolving Credit Facility \| Remaining Revolving Credit Facilities Maturing in November 2018
Debt Instrument [Line Items]
Collateral, number of vessels \| vessel		3
Minimum hull coverage ratios		105.00%
Actual hull coverage ratio	118.00%	150.00%	118.00%
Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Percentage of margin		2.00%	0.45%
Revolving Credit Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Percentage of margin		2.75%	2.75%
Remaining Revolving Credit Facilities \| Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Maintain the greater of free cash liquidity		$ 50,000,000
Minimum liquidity as a percentage of debt		5.00%
Remaining Revolving Credit Facilities \| Minimum \| Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Debt term		6 months
Remaining Secured Debt \| Minimum \| Guaranteed By Teekay Corporation
Debt Instrument [Line Items]
Debt term		6 months