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Sale of Additional Common Stock (Details) - Common Stock - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Mar. 31, 2018	Sep. 30, 2018
Sale of common stock	8,395,000	8,395,000
Net proceeds	$ 245.5

X

- Definition

Number of new stock issued during the period.

+ References

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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X

- Definition

Represents the aggregate value of stock proceeds from sale net of underwriting discounts, commissions and offering expenses.

+ References

No definition available.

+ Details

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Period Type:	duration

X

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