Derivatives And Risk Management (Interest Rate Swap Agreements) (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020 USD ($) Caontracts	Dec. 31, 2019 USD ($) Caontracts
Derivatives, Fair Value [Line Items]
Document Period End Date	Mar. 31, 2020
2020 | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Number of Interest Rate Derivatives Held | Caontracts	7	7
Derivative, Notional Amount | $	$ 70,000	$ 70,000
Mandatory Cash Settlement Date	2020	2020
2021 | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Number of Interest Rate Derivatives Held | Caontracts	4	3
Derivative, Notional Amount | $	$ 45,000	$ 35,000
Mandatory Cash Settlement Date	2021	2021
2022 | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Number of Interest Rate Derivatives Held | Caontracts	11	10
Derivative, Notional Amount | $	$ 120,000	$ 110,000
Mandatory Cash Settlement Date	2022	2022
2023 | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Number of Interest Rate Derivatives Held | Caontracts	1
Derivative, Notional Amount | $	$ 10,000
Mandatory Cash Settlement Date	2023