Share-Based Compensation and Employee Ownership Plans Stock Options (Details)		3 Months Ended
Dec. 05, 2016	Mar. 31, 2018 $ / shares	Dec. 31, 2017 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stockholders' Equity Note, Stock Split, Conversion Ratio	0.25
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate		0.00%
Aggregate Intrinsic Value
Closing stock price, in dollars per share		$ 13.20	$ 13.65

Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Roll Forward]

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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