Long-Term Debt (Credit Facility) (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 03, 2018	Mar. 09, 2018
Line of Credit Facility [Line Items]
Maximum secured borrowing capacity	$ 110,000,000
Percentage of maximum secured borrowing capacity	12.50%
Payments of notes payable	$ 2,000,000
Net deferred financing fees	1,376,000	$ 1,603,000
Amortization of deferred financing costs	$ 200,000	300,000	$ 300,000
New Markets Tax Credit (NMTC) Program [Member]
Line of Credit Facility [Line Items]
Net deferred financing fees					$ 700,000
PNC Bank [Member]
Line of Credit Facility [Line Items]
Minimum fixed charge coverage ratio				110.00%
PNC Bank [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Commitment fee on the daily unused portion of the Revolver	0.25%
Net deferred financing fees	$ 700,000	900,000
PNC Bank [Member] | Revolving Credit Facility [Member] | Restricted Cash [Member]
Line of Credit Facility [Line Items]
NMTC related restricted cash receipts	400,000	8,000,000
PNC Bank [Member] | Revolving Credit Facility [Member] | New Markets Tax Credit (NMTC) Program [Member]
Line of Credit Facility [Line Items]
Increase in maximum aggregate principal amount of borrowings	$ 6,700,000
PNC Bank [Member] | Revolving Credit Facility [Member] | LIBOR [Member]
Line of Credit Facility [Line Items]
Debt instrument, effective interest rate	3.45%
Amended and Restated Prior Credit Agreement [Member] | PNC Bank [Member]
Line of Credit Facility [Line Items]
Debt instrument, expiration date	Aug. 03, 2023
Amended and Restated Prior Credit Agreement [Member] | PNC Bank [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Maximum secured borrowing capacity				$ 110,000,000
Additional Credit Agreement [Member] | PNC Bank [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Net deferred financing fees		$ 400,000
Term Loan [Member] | PNC Bank [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Frequency of Periodic Payment	quarterly
Quarterly term loan payments	$ 400,000
Term Loan [Member] | PNC Bank [Member] | LIBOR [Member]
Line of Credit Facility [Line Items]
Debt instrument, effective interest rate	3.95%
Term Loan [Member] | Amended and Restated Prior Credit Agreement [Member] | PNC Bank [Member]
Line of Credit Facility [Line Items]
Maximum secured borrowing capacity				$ 10,000,000