Long-Term Debt (Schedule of Long-term Debt and Weighted Average Interest) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total principal	$ 58,590,000	$ 56,021,000
Deferred financing costs	(291,000)	(412,000)
Total long-term debt	58,299,000	55,609,000
Less current portion	(5,647,000)	(5,583,000)
Long-term portion	52,652,000	50,026,000
Credit Agreement - Bank of Montreal [Member]
Debt Instrument [Line Items]
Total principal	$ 39,682,000	$ 40,495,000
Weighted-average interest rate	4.13%	4.04%
Credit Agreements - CPL [Member]
Debt Instrument [Line Items]
Total principal	$ 0	$ 215,000
Weighted-average interest rate	0.00%	3.55%
Credit Agreements - SCCL [Member]
Debt Instrument [Line Items]
Total principal	$ 2,679,000	$ 0.00
Weighted-average interest rate	1.93%
Financing Obligation - CDR Land Lease [Member]
Debt Instrument [Line Items]
Total principal	$ 15,622,000	$ 14,520,000
Weighted-average interest rate	13.24%	13.54%
Capital Lease - CDR [Member]
Debt Instrument [Line Items]
Total principal	$ 607,000	$ 791,000
Weighted-average interest rate	7.04%	7.11%
Total Principal Debt [Member]
Debt Instrument [Line Items]
Weighted-average interest rate	6.61%	7.61%