Employee Benefit Plans (Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assumptions used to determine the benefit obligations
Discount rate	2.76%	3.46%
Rate of compensation increase	5.60%	5.60%
Assumptions used to determine net periodic benefit cost
Discount rate	3.46%	4.38%	3.76%
Rate of compensation increase	5.60%	5.60%	4.00%
Expected long-term rate of return on plan assets (percent)	7.50%	7.50%	7.50%