Income Taxes - Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Increase in valuation allowance before consideration of the Tax Act	$ 60,376	$ (5,713)
Increase due to the adoption of ASC 842	13,790	0
Other decrease during the year	(1,680)	0
Total increase (decrease) in valuation allowance before consideration of the Tax Act	72,486	(5,713)
Impact of the Tax Act on net operating loss usage	0	6,042
Total increase (decrease) in valuation allowance	$ 72,486	$ 329