Investments - Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Equity Securities, FV-NI, Gain (Loss) [Abstract]
Cost	$ 17,467		$ 17,467		$ 17,188
Gross Gains			507		154
Gross Losses			(21)		(14)
Fair Value	17,953		17,953		$ 17,328
Unrealized Gain (Loss) on Equity Securities [Abstract]
Recognized net gains (losses) on equity securities still held	$ 1,200	$ 100	$ 300	$ 200