Summary of Significant Accounting Policies Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 38,440	$ 48,488	$ 48,488
Total remaining discounted lease payments	$ 43,349	54,304
Deferred rent		(5,816)	$ (5,816)
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		54,304
Total remaining discounted lease payments		$ 54,304