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Share-Based Compensation - Summary of Weighted-Average Assumptions Used to Value Options (Details) - Employee Stock Option [Member]
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 0.99% 1.07% 1.17%
Dividend yield 0.00% 0.00% 0.00%
Expected life (years) 4 years 10 months 4 days 4 years 4 years
Volatility 56.96% 50.00% 42.56%
Forfeiture rate 5.85% 3.50% 2.20%