Aggregate number of common shares reserved for future issuance.

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-Name Accounting Standards Codification
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-Section S99
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Number of shares that have been repurchased during the period and are being held in treasury.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Employee Benefits and Share-Based Compensation - Summary of Shares Reserved for Future Issuance Under Equity Incentive Plans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares reserved for future issuance	9,465,000	9,465,000
Stock repurchases (in shares)	0	0	680,000
Stock repurchases price			$ 25,020
Share options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares reserved for future issuance	2,826,000	2,826,000
Non-vested restricted share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares reserved for future issuance	682,000	682,000
Shares authorized for future issuance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares reserved for future issuance	2,904,000	2,904,000
ESPP shares available for future issuance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total shares reserved for future issuance	3,053,000	3,053,000