Grant date of share-based payment award.

No definition available.

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- Definition

Vesting date of share-based payment award.

+ References

No definition available.

+ Details

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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.

+ Details

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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=96867065&loc=d3e5070-113901

+ Details

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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=96867065&loc=d3e5070-113901

+ Details

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Balance Type:	na
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- Definition

The weighted average fair value 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

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=96867065&loc=d3e5070-113901

+ Details

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Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Details

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Employee Benefit Plans - Restricted Shares Granted (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares	829,143	1,298,121	501,076
Grant Date Fair Value Per Share	$ 8.39	$ 5.70	$ 15.57
January 3, 2017 - 33% Per Year over Three Years [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Jan. 03, 2017
Shares	671,771
Grant Date Fair Value Per Share	$ 8.82
Vesting Percentage	33.00%
Vesting Period	3 years
January 3, 2017 - 100% on January 1, 2020 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Jan. 03, 2017
Shares	671,771
Grant Date Fair Value Per Share	$ 12.64
Vesting Percentage	100.00%
Vesting Date	Jan. 01, 2020
January 3, 2017 - 100% on January 1, 2019 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Jan. 03, 2017
Shares	9,956
Grant Date Fair Value Per Share	$ 8.82
Vesting Percentage	100.00%
Vesting Date	Jan. 01, 2019
April 3, 2017 - 100% on January 1, 2019 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Apr. 03, 2017
Shares	8,004
Grant Date Fair Value Per Share	$ 7.77
Vesting Percentage	100.00%
Vesting Date	Jan. 01, 2019
July 3, 2017 - 100% on January 1, 2019 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Jul. 03, 2017
Shares	14,018
Grant Date Fair Value Per Share	$ 5.64
Vesting Percentage	100.00%
Vesting Date	Jan. 01, 2019
October 2, 2017 - 100% on January 1, 2019 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Oct. 02, 2017
Shares	7,654
Grant Date Fair Value Per Share	$ 7.39
Vesting Percentage	100.00%
Vesting Date	Jan. 01, 2019
December 7, 2017 - 100% on December 7, 2018 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Date of Grant	Dec. 07, 2017
Shares	117,740
Grant Date Fair Value Per Share	$ 6.37
Vesting Percentage	100.00%
Vesting Date	Dec. 07, 2018