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

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- Definition

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

+ References

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

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
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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Summary of Significant Accounting Policies - Offering (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Jul. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Common stock, shares issued		62,082,348	54,040,000
July 2018 Offering
Common stock, shares issued	4,500,000
Stock issued (in dollars per share)	$ 20
Option for additional shares
Common stock, shares issued	675,000
July 2018 Offering inclusive of option for additional shares
Proceeds from issuance of common stock	$ 97.3
Payment of offering costs	$ 0.5