Revenue (Disaggregation of Revenue by Major Source) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Revenues		$ 19,100	$ 20,406
Service Revenues [Member]
Disaggregation of Revenue [Line Items]
Revenues		2,890	3,063
Terminal Services [Member]
Disaggregation of Revenue [Line Items]
Revenues		2,084	2,002
Trucking And Other [Member]
Disaggregation of Revenue [Line Items]
Revenues		806	1,061
Leasing Revenues [Member]
Disaggregation of Revenue [Line Items]
Revenues	[1]	16,210	17,343
Storage And Throughput Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	[1]	11,558	12,261
Railcar Transportation Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	[1]	$ 4,652	5,042
Terminal Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	[1]		$ 40

[1] Leasing revenues do not represent revenues recognized from contracts with customers under ASC 606, Revenue from Contracts with Customers, and are accounted for under ASC 842, Leases.