Debt - Cash Convertible Senior Subordinated Notes (Details) - USD ($) $ in Thousands		1 Months Ended	9 Months Ended
	Mar. 16, 2015	Mar. 31, 2010	Sep. 30, 2016	Sep. 30, 2015
Debt Disclosure [Abstract]
Issue of cash convertible senior subordinated notes		$ 375,000
Payment of convertible notes	$ 119,300		$ 0	$ 117,259
Payment of convertible notes, principal amount	117,300
Payment of convertible notes, interest portion	$ 2,100
Notes bear interest rate per year		3.50%