Employee Benefits and Share-Based Compensation - Stock Option Activity (Details) - 2009 Plan - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Shares
Outstanding at December 31, 2014	2,672
Granted (Awarded)	728
Exercised (Released)	(598)
Expired	(5)
Forfeited	(109)
Outstanding at December 31, 2015	2,688	2,672
Exercisable at December 31, 2015	1,399
Vested and expected to vest at December 31, 2015 and thereafter	2,648
Weighted Average Exercise Price
Outstanding at December 31, 2014	$ 19.02
Granted (Awarded)	31.21
Exercised (Released)	15.51
Expired	16.71
Forfeited	24.24
Outstanding at December 31, 2015	22.89	$ 19.02
Exercisable at December 31, 2015	17.74
Vested and expected to vest at December 31, 2015 and thereafter	$ 22.78
Outstanding at December 31 (in years)	6 years 11 months	6 years 6 months
Exercisable at December 31, 2014 (in years)	5 years 22 days
Vested and expected to vest at December 31, 2014 (in years)	6 years 11 months
Outstanding at December 31, 2015	$ 23,418
Exercisable at December 31, 2015	18,716
Vested and expected to vest at December 31, 2015 and thereafter	$ 23,332
Employee Stock Option
Weighted Average Exercise Price
Weighted-average fair value (in usd per share)	$ 9.67	$ 9.12	$ 8.09
Intrinsic value of options exercised	$ 11,300	$ 14,100	$ 14,000
Unrecognized compensation cost of unvested stock options	$ 11,200	$ 8,800
Weighted average period of compensation cost recognized	2 years 11 months	2 years 9 months 18 days