Fair Value of Financial Instruments (Amortized Cost Basis by Year of Origination and Credit Quality Indicator) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 2,746
2019	16,923
2018	25,523
Total	45,192
Current-period write-offs	0
Current-period recoveries	0
Current-period net write-offs	0
1-2 internal grade
Financing Receivable, Credit Quality Indicator [Line Items]
2020	2,746
2019	8,427
2018	18,935
Total	30,108
3-4 internal grade
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	8,496
2018	6,588
Total	15,084
5 internal grade
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
Total	0
6 internal grade
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
Total	0
7 internal grade
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
Total	$ 0