Derivative Financial Instruments (Summary Of Location And Amounts Of Derivative Fair Values In The Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Asset	$ 0	$ 667
Total return swap	1,690	785
Non-hedging derivatives [Member] | Interest rate swap agreements [Member] | Other Assets [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Asset	0	667
Total return swap	0	0
Non-hedging derivatives [Member] | Interest rate swap agreements [Member] | Other liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Asset	0	0
Total return swap	1,405	765
Non-hedging derivatives [Member] | Equity contracts [Member] | Other liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Asset	0	0
Total return swap	$ 285	$ 20