Accumulated Other Comprehensive Income (Reclassification out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Investments	$ (20,832)	$ (13)
Income tax expense (benefit)	8,703	$ (295)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	698
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Investments	698
Income tax expense (benefit)	$ 0