The number of vessels disposed off.

No definition available.

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- Definition

The weighted average exercise price at grant date for nonvested equity-based awards issued 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).

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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SUBSEQUENT EVENTS (Details) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
	Feb. 27, 2018 item $ / shares shares	Mar. 31, 2018 USD ($)	Dec. 31, 2017 shares	Dec. 31, 2016 shares	Dec. 31, 2015 shares
2015 EIP Plan \| Restricted Stock Units
Subsequent Events
Granted (in shares)			317,595	66,666	7,440
2015 EIP Plan \| Stock Options
Subsequent Events
Options to purchase (in shares)			133,000
Subsequent Event
Subsequent Events
Number of vessels disposed off \| item	9
Subsequent Event \| 2015 EIP Plan \| RSUs and Stock Options
Subsequent Events
Vesting percentage of awards	33.00%
Vesting period of awards	3 years
Subsequent Event \| 2015 EIP Plan \| Restricted Stock Units
Subsequent Events
Granted (in shares)	37,436
Subsequent Event \| 2015 EIP Plan \| Stock Options
Subsequent Events
Options to purchase (in shares)	122,608
Exercise price (in dollars per share) \| $ / shares	$ 13.69
Subsequent Event \| Forecast
Subsequent Events
Impairment loss \| $		$ 56,400