Summary of Significant Accounting Policies (Real Estate Investments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 01, 2013 Connecticut Warehouse [Member]	Dec. 31, 2012 Land [Member]	Dec. 31, 2012 Land, Buildings and Improvements [Member]	Dec. 31, 2012 Building and Building Improvements [Member]	Dec. 31, 2013 Minimum [Member]	Dec. 31, 2013 Maximum [Member]	Dec. 31, 2013 Land and Building [Member]	Dec. 31, 2012 Land and Building [Member]
Components of Real Estate Investments [Abstract]
Land	$ 18,892	$ 18,892
Buildings and improvements	59,256	55,011
Intangibles	329	329
Total real estate investment	78,477	74,232
Estimated useful life								5 years	39 years
Sale of warehouse building				9,200
Gain on sale of real estate investment	1,063	910	0	1,063
Selling expense				369
Assets Held-for-sale, Long Lived [Abstract]
Long-lived assets held for sale, gross					1,200	9,884	8,684
Accumulated depreciation, long-lived assets							2,116
Long-lived assets held-for-sale	0	7,768
Assets Leased or Available for Lease [Abstract]
Assets leased or available for lease										77,082	72,838
Operating Leases, Future Minimum Payments Receivable [Abstract]
2013	5,497
2014	5,616
2015	5,786
2016	5,883
2017	5,061
Thereafter	$ 31,817