The Company And Nature Of Operations (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Aug. 31, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2016	Feb. 29, 2016
Challenger [Member]
Business Acquisition [Line Items]
Acquisition purchase date			Feb. 01, 2016
Acquisition purchase price						$ 10.8
Hybrid [Member]
Business Acquisition [Line Items]
Acquisition purchase date			Jun. 01, 2016
Acquisition purchase price					$ 12.0
Series A Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred stock, dividend rate		8.50%	8.50%	8.50%
Series B Fixed-to-Floating Rate Cumulative Redeemable Perpetual Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred stock, dividend rate	8.50%		8.50%	8.50%