Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

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Per share or per unit amount of equity securities issued.

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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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No definition available.

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 04, 2015	Sep. 30, 2015	Jul. 29, 2015	Dec. 31, 2014
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued		27,231,583		22,802,039
Public offering price per share	$ 18.60
Net proceeds from offering of common stock	$ 75,231
Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued			3,763,440
Underwriters [Member] \| Maximum [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued	564,516