Number of Stock Appreciation Rights Tranches.

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- Definition

Retention ownership requirement percentage of participant.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options cancelled in period total fair value.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Conditions For Exercise Of Tranches Description

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- Definition

Share based compensation arrangement by share based payment award term.

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- Definition

Share based transaction fees capitalized to deferred financing fees.

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- Definition

Share based transaction fees capitalized to vessels.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Share-based compensation - Additional Information (Detail)		12 Months Ended
	Mar. 27, 2013 Tranche shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares of common stock reserved for issuance under the plan \| shares		3,000,000	2,000,000
Term of plan			10 years
Remaining shares left for issuance under this plan \| shares		1,418,715	578,598
Share-based compensation expenses		$ 3,928,000	$ 7,701,000	$ 14,004,000
Total unrecognized compensation costs relating to unvested share-based compensation awards		$ 1,956,000	3,041,000
Expected to be recognized over a weighted average period		17 months
Granted, stock appreciation rights \| shares				1,664,457
Share-based transaction fees capitalized to vessels		$ 4,753,000	3,662,000	$ 1,766,000
Transaction fees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses incurred		9,506,000	7,323,000	3,532,000
Arrangement fees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses incurred		8,627,000	4,520,000	6,631,000
Share-based arrangement fees capitalized to deferred financing fees		$ 4,314,000	2,260,000	2,666,000
Restricted shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Total fair value of shares vested		$ 1,028,000	831,000	935,000
Total fair value of shares cancelled		$ 82,000	$ 0	$ 71,000
Granted, stock appreciation rights \| shares		51,368	43,936	54,990
Phantom share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Outstanding phantom share units vested and available for exchange \| shares		547,001	560,334
Granted, stock appreciation rights \| shares		100,000	70,000	95,000
Stock appreciation rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, stock appreciation rights \| shares	1,664,457			1,664,457
Number of tranches \| Tranche	3
Stock appreciation rights (SARs) [Member] \| Common Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retention ownership percentage	50.00%
Stock appreciation rights (SARs) [Member] \| March 27, 2013 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conditions for exercise of tranches		If the fair market value of the common shares equals or exceeds the applicable base price for each tranche for any 20 consecutive trading days on or before the expiration date of each tranche
Retention requirement description		The common shares received on the exercise of SARs are subject to a retention requirement where the Participant is required to retain ownership of 50% of the net after tax number of shares until the later of March 22, 2018 or 120 days after the exercise date
Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Granted, stock appreciation rights \| shares		38,142	72,314
Retention requirement description		The restricted stock units generally vest over three years, in equal one-third amounts on each anniversary date of the date of the grant.
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expenses		$ 600,000	$ 600,000	$ 600,000