Leases Leases (Schedule of certain lease terms) (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Weighted average discount rate	3.56%	3.67%
Number of operating leases not yet commenced	0	1
Weighted average remaining lease term	13 years 3 months 18 days	14 years
Minimum [Member]
Range of lease expiration dates	1 year	4 months
Range of lease renewal options	1 year	1 year
Maximum [Member]
Range of lease expiration dates	21 years	21 years
Range of lease renewal options	5 years	5 years