Employee Benefit Plans (Schedule of Fair Value of Other Benefits Plan Assets) (Details) - Other Benefits Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Level 1 [Member]
Fair value of plan assets	$ 31,104	$ 27,220
Fair Value, Level 2 [Member]
Fair value of plan assets	13,788	13,393
Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member]
Fair value of plan assets	13,788	13,393
Mutual Funds [Member]
Fair value of plan assets	27,408	24,361
Mutual Funds [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets	27,408	24,361
Mutual Funds [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets
Mutual Funds [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets
Money Market Funds [Member]
Fair value of plan assets	3,696	2,859
Money Market Funds [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets	3,696	2,859
Money Market Funds [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets
Money Market Funds [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets
Debt Securities [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets	13,788	13,393
Debt Securities [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets