Summary of Significant Accounting Policies - Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash paid for:
Interest	$ 8,817	$ 3,743	$ 2,832
Income taxes	$ 45,288	$ 33,401	$ 38,144