Percentage of repurchase of class A common stock.

No definition available.

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- Definition

Stock Repurchased and Retired During Period, Per Share

+ References

No definition available.

+ Details

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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

Face amount or stated value per share of common stock.

+ References

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- Definition

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

+ References

+ Details

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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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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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.

+ References

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased and retired during the period.

+ 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(28))
-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 S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: 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=6928386&loc=d3e21463-112644

Reference 4: 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

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

Reference 1: 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=6928386&loc=d3e21463-112644

Reference 2: 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Share Capital - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
Share Capital - Narrative (Details) - USD ($)	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	May 05, 2017	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 15, 2015
Class of Stock [Line Items]
Preferred stock, authorized (in shares)	50,000,000		50,000,000
Preferred stock, par value (dollars per share)	$ 0.001		$ 0.001
Preferred stock, issued (in shares)	0		0
Class A Stock [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	50,000,000		50,000,000				50,000,000
Common stock, par value (dollars per share)	$ 0.001		$ 0.001				$ 0.001
Common stock, shares issued (in shares)	13,132,775		13,132,775				13,261,095
Common stock, shares outstanding (in shares)	13,132,775	13,259,715	13,132,775	13,259,715		13,182,332	13,261,095	13,263,532	13,238,486
Repurchased and canceled pursuant to the stock buy-back (in shares)	49,557	10,980	307,340	251,254
Class A Stock [Member] \| New Program [Member]
Class of Stock [Line Items]
Common stock, shares issued (in shares)					13,178,571
Common stock, shares outstanding (in shares)					13,178,571
Number of shares authorized to be repurchased (in shares)					650,000
Stock Repurchase Program Percentage Of Shares Repurchase Of Outstanding Share					5.00%
Repurchased and canceled pursuant to the stock buy-back (in shares)	49,557		307,340
Stock repurchased and retired during period, value	$ 801,700		$ 5,200,000
Stock repurchased and retired during period (dollars per share)	$ 16.18		$ 16.78
Remaining number of shares authorized to be repurchased (in shares)	651,916		651,916		690,734
Class A Stock [Member] \| Previous Program [Member]
Class of Stock [Line Items]
Number of shares authorized to be repurchased (in shares)										665,000
Remaining number of shares authorized to be repurchased (in shares)										40,734
Class B Stock [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	99,665		99,665				99,665
Common stock, par value (dollars per share)	$ 0.001		$ 0.001				$ 0.001
Common stock, shares issued (in shares)	99,665		99,665				99,665
Common stock, shares outstanding (in shares)	99,665		99,665				99,665