Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB

-Name Accounting Standards Codification

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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-Name Regulation S-X (SX)

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Share-based compensation - Schedule of management and director options activity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2011	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share compensation expenses	$ 2,481	$ 4,143	$ 0	$ 6,979	$ 7,611	$ 9,800	$ 6,408
Number of options (in shares)
Outstanding (in shares)				10,981,075	10,956,838	10,956,838	0
Forfeited (in shares)						(324,599)	0
Exercised (in shares)				(60,000)		0	0
Outstanding (in shares)	11,269,911		0	11,269,911		10,981,075	10,956,838
Weighted average exercise price (in dollars per share)
Outstanding (in dollars per share)				$ 13.23	$ 13.20	$ 13.20	$ 0.00
Forfeited (in dollars per share)						$ 13.20	$ 0.00
Exercised (in dollars per share)				$ 10.00
Outstanding (in dollars per share)	$ 13.40		$ 0.00	$ 13.40		$ 13.23	$ 13.20
Management
Number of options (in shares)
Granted (in shares)				348,836		348,836	10,872,090
Weighted average exercise price (in dollars per share)
Granted (in dollars per share)				$ 18.25		$ 14.09	$ 13.20
Director
Number of options (in shares)
Granted (in shares)						0	84,748
Weighted average exercise price (in dollars per share)
Granted (in dollars per share)							$ 13.20
Management and director options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share compensation expenses	$ 1,700	$ 3,700		$ 5,100	$ 6,500	$ 8,300	$ 4,800
Number of options (in shares)
Outstanding (in shares)				10,981,075
Outstanding (in shares)	11,269,911			11,269,911		10,981,075
Weighted average exercise price (in dollars per share)
Outstanding (in dollars per share)				$ 13.23
Outstanding (in dollars per share)	$ 13.40			$ 13.40		$ 13.23