Stock-Based Compensation Stock-Based Compensation Details (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Stock-Based Compensation Details
Employee Benefits and Share-based Compensation	$ 970	$ (30)
Minimum [Member]
Stock-Based Compensation Details
Equity Share Payout Range	0
Maximum [Member]
Stock-Based Compensation Details
Equity Share Payout Range	48,291
Share-based Compensation Award, Tranche Two [Member]
Stock-Based Compensation Details
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	44,737
Share Based Compensation Non Option Equity Instruments Granted Weighted Average Exercise Price	$ 24.70

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- Definition

Share Based Compensation Non Option Equity Instruments Granted Weighted Average Exercise Price

+ References

No definition available.

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- Definition

Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

+ 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=66902209&loc=d3e3602-108585

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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

Net number of non-option equity instruments granted to participants.

+ 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)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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