Employee Benefits (Schedule Of Fair Value Of Pension Plan Assets) (Details) - U. S. Plans [Member] - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 50,763	$ 53,415	$ 49,236
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		50,763	53,415
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets			622
Bank Collective Trust Funds - Equity Securities [Member] | Large-Cap Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	18,384	19,473
Bank Collective Trust Funds - Equity Securities [Member] | Small-Cap Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[2]	4,069	3,351
Bank Collective Trust Funds - Equity Securities [Member] | International Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[3]	8,181	8,474
Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | Large-Cap Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	18,384	19,473
Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | Small-Cap Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[2]	4,069	3,351
Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | International Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[3]	8,181	8,474
Bank Collective Trust Funds - Fixed Income [Member] | Bond Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[4]	19,624	21,495
Bank Collective Trust Funds - Fixed Income [Member] | Short Term Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		505	622
Bank Collective Trust Funds - Fixed Income [Member] | Level 2 [Member] | Bond Index Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[4]	$ 19,624	$ 21,495

[1] (1)Substantially all of the assets of these funds are invested in large-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.

[2] (2)Substantially all of the assets of these funds are invested in small-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.

[3] (3)Substantially all of the assets of these funds are invested in international companies in developed markets (excluding the United States and Canada). The remainder of the assets of these funds is invested in cash reserves.

[4] (4)This category represents investment grade bonds of U.S. issuers, including U.S. Treasury notes.