Schedule II - Valuation and Qualifying Accounts - Deferred Tax Valuation Allowance (Details) - Deferred Tax Valuation Allowance - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 722	$ 1,280	$ 1,082
Additions	5,556	331	198
Reductions	(251)	(889)	0
Other	0	0	0
Balance at end of year	$ 6,027	$ 722	$ 1,280