Stockholders' Equity (Details 1) - Public Offering - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Subsidiary, Sale of Stock [Line Items]
Shares Issued		0	23,000,000	0
Gross Proceeds Per Share (USD per share)	$ 7.85		$ 7.85
Gross Proceeds			$ 180,550
Issuance costs	$ 0		$ 412

The cash outflow for cost incurred directly with the issuance of an equity security.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Cash received on stock transaction after deduction of issuance costs.

+ References

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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