Equity-Based Compensation (Aggregate Intrinsic Value of Options Exercised and Aggregate Fair Value of Restricted Stock Units and Restricted Shares that Vested) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 2,439	$ 1,089	$ 326
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of vested share-based payment award	4,368	6,578	2,416
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of vested share-based payment award	247	111	364
Deferred stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of vested share-based payment award	$ 443	$ 0	$ 0

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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