Derivative Instruments and Hedging Activities Derivative Gain (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Interest Rate Swap No. 2 [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative, term of contract	5 years	5 years
Fair value of interest rate derivatives	$ (368)
Unrealized gain (loss) on interest rate cash flow hedges	$ 191	$ (121)
Interest Rate Swap No. 1 [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative, term of contract	10 years	10 years
Fair value of interest rate derivatives	$ (2,123)	$ (1,054)
Unrealized gain (loss) on interest rate cash flow hedges	478	60
Interest Rate Swap [Member]
Derivative Instruments Gain Loss [Line Items]
Fair value of interest rate derivatives	(2,491)	(1,054)
Unrealized gain (loss) on interest rate cash flow hedges	$ 669	$ (61)