CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
CONDENSED CONSOLIDATED BALANCE SHEETS
Preferred stock, no par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares outstanding (in shares)	0	0
Common shares, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares issued (in shares)	66,801,270	65,640,607
Common stock, shares outstanding (in shares)	66,801,270	65,640,607

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

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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

+ Details

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

+ Details

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- Definition

Face amount per share of no-par value preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

+ Details

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

+ Details

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- References

No definition available.

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