Stockholders' Equity (Narratives) (Details) - $ / shares	3 Months Ended
Jun. 30, 2018	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Dividends payable, date declared	Jun. 06, 2018	Mar. 08, 2018
Dividends payable, amount per share	$ 0.5	$ 0.5
Dividends payable, date of record	Jun. 21, 2018	Mar. 23, 2018
Dividends payable, date to be paid	Jul. 05, 2018	Apr. 06, 2018

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

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

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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- Definition

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

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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.

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- References

No definition available.

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