Fair Value of Financial Instruments (Level 3 Securities) (Details) - Recurring - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 1,589	$ 1,511
Net unrealized gains	53	131
Purchases	100	0
Disposals	(100)	0
Ending Balance	1,642	1,642
Corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	250	250
Net unrealized gains	0	0
Purchases	100	100
Disposals	(100)	(100)
Ending Balance	250	250
Asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	744	666
Net unrealized gains	53	131
Purchases	0	0
Disposals	0	0
Ending Balance	797	797
Equities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	595	595
Net unrealized gains	0	0
Purchases	0	0
Disposals	0	0
Ending Balance	$ 595	$ 595