Schedule III: Rollforward of Real Estate Assets and Accumulated Depreciation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of carrying amount of real estate investments rollforward
Balance at the beginning of period	$ 911,792	$ 906,907	$ 897,312
Subtotal real estate	919,576	911,792	906,907
Less: Fully depreciated assets	0	0	0
Balance at the end of the period	919,576	911,792	906,907
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at the beginning of period	160,826	136,460	112,765
Real Estate Accumulated Depreciation, Depreciation Expense	24,549	24,366	23,695
Subtotal of accumulated depreciation	185,375	160,826	136,460
Less: Fully depreciated assets	0	0	0
Balance at the end of the period	185,375	160,826	136,460
Land Improvements [Member]
Reconciliation of carrying amount of real estate investments rollforward
Real Estate, Improvements	0	0	0
Building Improvements [Member]
Reconciliation of carrying amount of real estate investments rollforward
Real Estate, Improvements	5,072	3,776	49,027
Construction in Progress [Member]
Reconciliation of carrying amount of real estate investments rollforward
Real Estate, Improvements	$ 2,712	$ 1,109	$ (39,432)