Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Addition of operating lease asset included in accrued expenses and other current liabilities	$ 532	$ 562	$ 0	$ 0
Operating lease liabilities arising from obtaining operating lease assets	$ 17,144