Summary of Accounting Policies - Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($) investment_type	Mar. 31, 2019 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of types of investments | investment_type		2
Payments to acquire equity securities	$ 2,000
Advertising expense		$ 22,529	$ 30,234
Advertising production costs		$ 174	$ 48