Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=79507207&loc=d3e4534-113899

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11149-113907

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11178-113907

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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)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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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

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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

Percentage of vesting of share-based compensation awards.

+ 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)
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Stock Based Compensation - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 3,181
Stock based compensation expense	3,181	$ 1,676
Allocated Share-based Compensation Expense	$ 0
One Year Vesting Restricted Stock [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	36,317
One Year Vesting Restricted Stock [Member] \| Share-based Compensation Award, Tranche One \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	100.00%
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	237,281
Restricted stock \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	21,928
Two Year Vesting Restricted Stock, March Schedule \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	4,767
Two Year Vesting Restricted Stock, March Schedule \| Share-based Compensation Award, Tranche One \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	50.00%
Two Year Vesting Restricted Stock, March Schedule \| Share-based Compensation Award, Tranche Two \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	50.00%
Three Year Vesting Restricted Stock [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	26,321
Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	426,075
Three Year Vesting Restricted Stock, March Schedule [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	373,432
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	52,643
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche One \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche One \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche Three \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Two Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	31,464
Two Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche One \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	50.00%
Two Year Vesting Restricted Stock, Grant Date Schedule [Member] \| Share-based Compensation Award, Tranche Two \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	50.00%
Three Year Vesting Restricted Stock, March Schedule [Member] \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of stock (in shares)	116,484
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche One \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche Two \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Three Year Vesting Restricted Stock, March Schedule [Member] \| Share-based Compensation Award, Tranche Three \| Other Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, vesting percentage	33.33%
Additional Paid-in Capital [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 3,176