Subordinated Debt - Schedule Of Subordinated Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 525,153	$ 410,176
Unamortized discounts and debt issuance costs	(1,125)	(1,274)
Subordinated Debt
Debt Instrument [Line Items]
Long-term debt	35,000	38,000
Unamortized discounts and debt issuance costs	(1,125)	(1,274)
Subordinated Debt | 8% Debenture Due 2021
Debt Instrument [Line Items]
Long-term debt	0	3,000
Unamortized discounts and debt issuance costs	0	0
Subordinated Debt | 6.4375% Notes Due 2025
Debt Instrument [Line Items]
Long-term debt	10,000	10,000
Unamortized discounts and debt issuance costs	(162)	(186)
Subordinated Debt | 6% Notes Due 2021
Debt Instrument [Line Items]
Long-term debt	25,000	25,000
Unamortized discounts and debt issuance costs	$ (963)	$ (1,088)