Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018
Summary of Significant Accounting Policies
Lease, Practical Expedients, Package [true false]	true
Lease, Practical Expedient, Use of Hindsight [true false]	false
Operating Lease, Right-of-Use Asset	$ 55,600	$ 51,129	$ 0
Operating Lease, Liability	65,800	$ 61,061
Deferred rent	9,300
Sublease loss	2,400
Intangible assets	$ 1,500