Share-Based Compensation (Details 1) - $ / shares	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Stock Issued or Granted During Period, Share-based Compensation
Number of service-based options granted	54,000	62,500	373,250	491,400
Weighted average grant date fair value	$ 6.56	$ 6.75	$ 6.86	$ 7.94
Weighted average exercise price	$ 13.05	$ 14.18	$ 13.7	$ 16.75

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration