Quarterly report pursuant to Section 13 or 15(d)

Deferred Costs - Additional Information (Details)

v3.19.2
Deferred Costs - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]          
Amortization of intangible assets $ 2,410 $ 4,090 $ 5,040 $ 8,400  
Finite-lived intangible assets, accumulated amortization $ 53,590   $ 53,590   $ 50,550