Line of credit facility maximum borrowing capacity option to increase.

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- Definition

Notice period required for early redemption of notes.

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No definition available.

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Number of reducing revolving credit facilities.

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Number Of Revolving Credit Facilities

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Number of term loan credit facilities.

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- Definition

Number of vessels in process of being released from security.

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- Definition

Number of vessels secured by first-priority mortgages.

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No definition available.

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- Definition

Term loan line of credit facility description.

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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.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

+ References

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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.

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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

+ References

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- Definition

Amount of increase (decrease) of the credit facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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No definition available.

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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- Definition

The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Long-term Debt - Additional Information (Detail) - Seaspan [Member]				1 Months Ended	12 Months Ended
	Dec. 30, 2019 USD ($)	Sep. 18, 2019 USD ($)	May 15, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Vessel CreditFacility	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Number of vessels secured by first-priority mortgages \| Vessel					62
Number of vessels in process of being released from security \| Vessel					1
Secured Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum aggregate borrowings			$ 1,000,000,000
Option to increase in amount of maximum aggregate borrowings			2,000,000,000
Credit facilities, increase in maximum aggregate borrowings		$ 500,000,000
Senior Unsecured Notes Due 2019 [Member]
Debt Instrument [Line Items]
Maturity date				Apr. 30, 2019
Debt instrument, interest rate				6.375%		6.375%
Repurchase of senior unsecured notes					$ 8,998,000
Repayment of principal balance of term loan					311,398,000
Term Loans [Member]
Debt Instrument [Line Items]
Credit facilities, maximum aggregate borrowings				$ 2,158,743,000	1,954,375,000	$ 2,158,743,000
Credit facilities, aggregate borrowings undrawn					155,000,000
Prepayment of remaining balance of long-term debt					$ 1,101,037,000
Weighted average rate of interest, including the margin				4.80%	4.00%	4.80%
Maturity date	Dec. 30, 2025
Number of term loan credit facilities \| CreditFacility					15
Term Loan Line Of Credit Facility Description					Term Loan payments are made in quarterly or semi-annual payments commencing three, six or thirty-six months after delivery of the associated newbuilding containership, utilization date or the inception date of the Term Loan.
Credit facilities, borrowing amount	$ 155,000,000
Term Loans [Member] \| Export-Import Bank Of Korea [Member]
Debt Instrument [Line Items]
Interest rate margin					0.70%	0.70%
Principal outstanding amount				$ 65,515,000	$ 52,743,000	$ 65,515,000
Term Loans [Member] \| Secured Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum aggregate borrowings			$ 800,000,000
Maturity date			May 15, 2024
Credit facilities, increase in maximum aggregate borrowings		400,000,000
Secured Term Loans Credit Facilities [Member]
Debt Instrument [Line Items]
Prepayment of remaining balance of long-term debt					$ 259,401,000
Number of term loan credit facilities \| CreditFacility					6
Minimum [Member] \| 2025 Notes and 2026 Notes [Member] \| Fairfax Financial Holdings Limited [Member]
Debt Instrument [Line Items]
Notice period required for early redemption of notes					120 days
Maximum [Member] \| 2025 Notes and 2026 Notes [Member] \| Fairfax Financial Holdings Limited [Member]
Debt Instrument [Line Items]
Notice period required for early redemption of notes					150 days
Maximum [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Credit facilities, increase in maximum aggregate borrowings	$ 100,000,000
One Month LIBOR [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
LIBOR interest rate				2.40%	1.90%	2.40%
LIBOR Plus Margin [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Interest rate description					interest calculated as one month, three month or six month LIBOR plus a margin per annum
Debt instrument description					At December 31, 2019, the one month, three month and six month average LIBOR was 1.9%, 2.0% and 2.1%, respectively (2018 – 2.4%, 2.6% and 2.5%, respectively) and the margins ranged between 0.4% and 4.3% (2018 – 0.4% and 4.8%) for Term Loans.
Principal outstanding amount					$ 1,746,632,000
LIBOR Plus Margin [Member] \| Minimum [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Interest rate margin					0.40%	0.40%
LIBOR Plus Margin [Member] \| Maximum [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
Interest rate margin					4.30%	4.80%
Three Month LIBOR [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
LIBOR interest rate				2.60%	2.00%	2.60%
Six Month LIBOR [Member] \| Term Loans [Member]
Debt Instrument [Line Items]
LIBOR interest rate				2.50%	2.10%	2.50%
Revolving Credit Facilities [Member]
Debt Instrument [Line Items]
Number of long-term revolving credit facilities \| CreditFacility					4
Credit facilities, maximum aggregate borrowings				$ 938,209,000	$ 987,012,000	$ 938,209,000
Credit facilities, aggregate borrowings undrawn				$ 150,011,000	120,000,000	$ 150,011,000
Prepayment of remaining balance of long-term debt					$ 205,946,000
Number of reducing revolving credit facilities \| CreditFacility					2
Interest rate description					Interest is calculated based on one month LIBOR plus a margin per annum
Debt instrument description					At December 31, 2019, the one month average LIBOR was 1.8% (2018 – 2.4%) and the margins ranged between 0.5% and 2.25% (2018 – 0.5% and 1.4%) for the Revolvers.
Weighted average rate of interest, including the margin				3.00%	2.90%	3.00%
Description of the terms of a credit facility arrangement					For secured facilities, Revolver payments are made in semi-annual payments commencing thirty-six months after delivery of the associated newbuilding containership
Maturity date					Dec. 31, 2023
Revolving Credit Facilities [Member] \| Secured Credit Facility [Member]
Debt Instrument [Line Items]
Credit facilities, maximum aggregate borrowings			$ 200,000,000
Maturity date			May 15, 2022
Credit facilities, increase in maximum aggregate borrowings		$ 100,000,000
Revolving Credit Facilities [Member] \| Term Loan Payment Due in Full Maturity [Member]
Debt Instrument [Line Items]
Principal outstanding amount					$ 58,240,000
Revolving Credit Facilities [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate margin					0.50%	0.50%
Commitment fee on undrawn amount					0.20%	0.20%
Revolving Credit Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate margin					2.25%	1.40%
Commitment fee on undrawn amount					0.50%	0.50%
Revolving Credit Facilities [Member] \| One Month LIBOR [Member]
Debt Instrument [Line Items]
LIBOR interest rate				2.40%	1.80%	2.40%
Revolving Credit Facilities Two [Member]
Debt Instrument [Line Items]
Description of the terms of a credit facility arrangement					Revolver with a principal outstanding of $180,000,000, will be converted into a term loan facility on May 15, 2022 (note 9(c))
Principal outstanding amount					$ 180,000,000
Maturity date					May 15, 2022