Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Sales | Debt Securities | Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	$ 31,928	$ 42,874
Gross Realized Gains	1,252	3,495
Gross Realized Losses	(46)	(1,162)
Net Realized Gain (Loss)	1,206	2,333
Sales | Equity Securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	152,170	52,533
Gross Realized Gains	50,656	19,569
Gross Realized Losses	(1,784)	(6,732)
Net Realized Gain (Loss)	48,872	12,837
Calls/Maturities | Debt Securities | Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	204,960	121,911
Gross Realized Gains	406	294
Gross Realized Losses	(63)	(9)
Net Realized Gain (Loss)	$ 343	$ 285