Stock-Based Compensation - Schedule of Stock Appreciation Rights (SARs) (Details) - Stock Appreciation Rights (SARs) - shares	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Stock Appreciation Rights
Nonvested, Beginning Balance (in shares)	209,962	379,495
Granted (in shares)	0	0
Canceled (shares)	(138,526)	(169,533)
Nonvested, Ending Balance (in shares)	71,436	209,962

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cancellations in Period

No definition available.

+ 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

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ 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)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Details

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