Annual report pursuant to Section 13 and 15(d)

Intangible Assets - Additional Information (Details)

v3.6.0.2
Intangible Assets - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]      
Impairment of intangible assets, indefinite-lived (excluding goodwill) $ 0 $ 0 $ 0
Impairment of definite-lived intangible assets 0 0 0
Amortization of intangible assets $ 48,545,000 $ 51,700,000 $ 55,016,000