Fair Value of Financial Instruments (Level 3 Securities) (Details) - Recurring $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 1,771
Net unrealized gains (losses)	(78)
Transfers out	(100)
Ending balance	1,593
Corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	250
Net unrealized gains (losses)	0
Transfers out	(100)
Ending balance	150
Asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	926
Net unrealized gains (losses)	(78)
Transfers out	0
Ending balance	848
Equities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	595
Net unrealized gains (losses)	0
Transfers out	0
Ending balance	$ 595