Fair Value Measurements and Derivative Instruments (Schedule of Fair Value Assets and (Liabilities) Carried at Fair Value and Measured on Recurring Basis) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative asset	$ 975	$ 391
Convertible debt	(1,050)	(1,069)
Total	(75)	(678)
Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total	709	77
Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Convertible debt	(1,050)	(1,069)
Total	(784)	(755)
Interest Rate Derivatives [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative asset	709	77
Interest Rate Derivatives [Member] | Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative asset	709	77
Series E Preferred Embedded Redemption Option [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative asset	266	314
Series E Preferred Embedded Redemption Option [Member] | Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative asset	$ 266	$ 314