Investments In Direct Financing Lease (Narrative) (Details) - Real Estate, Property Type [Domain]		6 Months Ended		12 Months Ended
	May. 22, 2015 USD ($) properties	Jun. 30, 2015 USD ($) years properties	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) properties	May. 21, 2015 USD ($)
number of properties sold | properties	1
Net Investment in Direct Financing and Sales Type Leases		$ 189,203,000		$ 199,332,000	$ 4,700,000
originalacquisitioncost					$ 4,100,000
Capital Leases, Net Investment in Direct Financing Leases, Initial Direct Costs		1,400,000		1,500,000
Allowance for lease losses		0		$ 0
Payments to Acquire Productive Assets		334,700,000
Proceeds from Sale of Property, Plant, and Equipment	$ 4,700,000
Gain (Loss) on Disposition of Property Plant Equipment	$ 0
Gain (Loss) on Contract Termination		$ 100,000	$ 100,000
Minimum [Member]
Length of lease (in years) | years		17
Maximum [Member]
Length of lease (in years) | years		20
Imagine Schools [Member]
Number of public charter school properties (in properties) | properties		21		23
Gain (Loss) on Contract Termination		$ 0