Stockholders' Equity - Public Offering (Details) - Public Offering $ / shares in Units, shares in Thousands, $ in Thousands	May 10, 2017 USD ($) $ / shares shares
Subsidiary, Sale of Stock [Line Items]
Shares Issued \| shares	23,000
Gross Proceeds Per Share \| $ / shares	$ 7.85
Gross proceeds	$ 180,550
Stock issuance costs	$ 2,300

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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- Definition

Amount of consideration received by subsidiary or equity investee in exchange for shares of stock issued or sold. Includes amount of cash received, fair value of noncash assets received, and fair value of liabilities assumed by the investor.

+ References

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- Definition

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

+ References

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- Definition

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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- 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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