CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Shareholders’ Equity:
Preferred share capital, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred share capital, authorized (in shares)	50,000,000	50,000,000
Preferred share capital, issued (in shares)	0	0
Common Class A
Shareholders’ Equity:
Common Stock, par value per share	$ 0.10	$ 0.10
Ordinary share capital, authorized (in shares)	100,000,000	100,000,000
Ordinary share capital, issued (in shares)	31,104,830	31,111,432
Ordinary share capital, outstanding (in shares)	31,104,830	31,111,432
Common Class B
Shareholders’ Equity:
Common Stock, par value per share	$ 0.10	$ 0.10
Ordinary share capital, authorized (in shares)	25,000,000	25,000,000
Ordinary share capital, issued (in shares)	6,254,715	6,254,895
Ordinary share capital, outstanding (in shares)	6,254,715	6,254,895

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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.

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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

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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