Basis of Accounting and Consolidation Basis of Accounting and Consolidation (Stock Plans) (Details) - shares	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares to be issued in stock incentive plan (in shares)	149,983		149,983
Employee Stock Purchase Plan [Abstract]
Employee Discount for Employee Stock Purchase Plan			5.00%
Employee Stock Purchase Plan, Number Of Shares Authorized	600,000		600,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans	0	0	2,858	782
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock awarded in SI plan (in shares)			10,500		13,250
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock awarded in SI plan (in shares)			15,540		28,700