Basis of Presentation (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Basis of Presentation [Abstract]
Dividends Payable, Date Declared	Aug. 08, 2017
Dividends Payable, Date of Record	Aug. 22, 2017
Dividends Payable, Date to be Paid	Sep. 15, 2017
Common Stock, Dividend Rate, Percentage		50.00%

The percentage rate used to calculate dividend payments on common stock.

No definition available.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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