Common Shares (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2015	Dec. 30, 2017	Dec. 31, 2016
Common Shares
Common Stock Shares Issued	16,670,000	86,757,334	85,743,958
Common Stock, No Par Value	$ 0	$ 0	$ 0
Shares Issued Price Per Share	$ 6
Proceeds From Issuance Or Sale Of Equity	$ 100.0
Payments Of Stock Issuance Costs	4.4
Income Tax Effects Allocated Directly To Equity - Equity Transactions	$ 1.6

Face amount per share of no-par value common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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- Definition

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.

+ References

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- References

No definition available.

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- Definition

The tax effect of an increase or decrease in contributed capital (for example, deductible expenditures reported as a reduction of the proceeds from issuing capital stock) during the period charged or credited directly to shareholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79507043&loc=d3e39076-109324

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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