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://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Period Type:	duration

- Details

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Subsequent Events - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Nov. 09, 2018	Sep. 30, 2018	Mar. 31, 2018
Subsequent Event [Line Items]
Common stock, shares issued		115,200,421	111,032,957
At-The-Market Facility [Member]
Subsequent Event [Line Items]
Common stock, shares issued		3,762,130
Net proceeds from sale of common stock		$ 5.1
Subsequent Event [Member] \| At-The-Market Facility [Member]
Subsequent Event [Line Items]
Common stock, shares issued	741,298
Net proceeds from sale of common stock	$ 0.8