Schedule IV - Mortgage Loans on Real Estate (Details) (USD $)	12 Months Ended
	Dec. 31, 2013
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	$ 349,300,000
Face Amount of Mortgages	399,700,000
Carrying Amount December 31, 2013	401,800,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2017 [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	25,400,000
Face Amount of Mortgages	29,000,000
Carrying Amount December 31, 2013	29,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2017 [Member] | LIBOR [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	2.00%
Mortgage Loan Payable Due 2014 [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	7,000,000
Face Amount of Mortgages	7,000,000
Carrying Amount December 31, 2013	7,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2014 [Member] | LIBOR [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	3.50%
Mortgage Loan Payable Due 2013 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	600,000
Face Amount of Mortgages	600,000
Carrying Amount December 31, 2013	600,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2013 [Member] | Prime Rate [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	1.00%
6.75% Mortgage Loan Payable Due 2016 [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	6.75%
Balloon Amount	12,000,000
Face Amount of Mortgages	12,000,000
Carrying Amount December 31, 2013	12,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2016 LIBOR Plus Two Percent [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	18,500,000
Face Amount of Mortgages	18,700,000
Carrying Amount December 31, 2013	18,700,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2016 LIBOR Plus Two Percent [Member] | LIBOR [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	2.00%
4.98% Retail Mortgage Note Payable Due 2018 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.79%
Balloon Amount	3,600,000
Face Amount of Mortgages	4,000,000
Carrying Amount December 31, 2013	3,900,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
5% Retail Mortgage Loan Payable Due 2015 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	5.00%
Balloon Amount	2,900,000
Face Amount of Mortgages	3,900,000
Carrying Amount December 31, 2013	3,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Retail Mortgage Loan Payable Due 2015 PRIME Plus Point Five Percent [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	4,500,000
Face Amount of Mortgages	4,900,000
Carrying Amount December 31, 2013	4,800,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Retail Mortgage Loan Payable Due 2015 PRIME Plus Point Five Percent [Member] | Prime Rate [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	0.50%
4.1% Retail Mortgage Loan Payable Due 2020 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.10%
Balloon Amount	10,600,000
Face Amount of Mortgages	12,400,000
Carrying Amount December 31, 2013	12,300,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
5.75% Retail Mortgage Loan Payable Due 2020 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	5.75%
Balloon Amount	6,100,000
Face Amount of Mortgages	8,100,000
Carrying Amount December 31, 2013	8,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
5% Retail Mortgage Loan Payable Due 2023 [Member] | Retail [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	5.00%
Balloon Amount	6,000,000
Face Amount of Mortgages	7,300,000
Carrying Amount December 31, 2013	7,300,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
1.77% Commercial building Mortgage Loan Payable Due 2016 [Member] | Commercial Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	1.77%
Balloon Amount	2,400,000
Face Amount of Mortgages	2,400,000
Carrying Amount December 31, 2013	2,400,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Loan Payable Due 2022 [Member] | Apartment Building [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	19,500,000
Face Amount of Mortgages	23,500,000
Carrying Amount December 31, 2013	23,500,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	178
Mortgage Loan Payable Due 2022 [Member] | Adjustable Rate [Member] | Apartment Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	2.07%
3.35% Mortgage Loan Payable Due 2023 [Member] | Multifamily Properties [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	3.35%
Balloon Amount	21,000,000
Face Amount of Mortgages	26,000,000
Carrying Amount December 31, 2013	26,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	217
4.71% Mortgage Loan Payable Due 2020 [Member] | Apartment Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.71%
Balloon Amount	22,700,000
Face Amount of Mortgages	26,300,000
Carrying Amount December 31, 2013	27,400,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	366
5.43% Mortgage Loan Payable Due 2020 [Member] | Apartment Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	5.43%
Balloon Amount	4,600,000
Face Amount of Mortgages	5,300,000
Carrying Amount December 31, 2013	5,700,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	366
4.19% Mortgage Loan Payable Due 2018 [Member] | Apartment Building [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.19%
Balloon Amount	13,000,000
Face Amount of Mortgages	14,400,000
Carrying Amount December 31, 2013	14,300,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	204
4.31% Mortgage Loan Payable Due 2020 [Member] | Multifamily Properties [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.31%
Balloon Amount	60,300,000
Face Amount of Mortgages	70,800,000
Carrying Amount December 31, 2013	71,900,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	615
4.64% Mortgage Loan Payable Due 2020 [Member] | Multifamily Properties [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.64%
Balloon Amount	16,800,000
Face Amount of Mortgages	19,300,000
Carrying Amount December 31, 2013	20,200,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	615
3.58% Mortgage Loan Payable Due 2023 [Member] | Multifamily Properties [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	3.58%
Balloon Amount	41,100,000
Face Amount of Mortgages	49,700,000
Carrying Amount December 31, 2013	49,700,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	450
4.93% Mortgage Loan Payable Due 2026 [Member] | Multifamily Properties [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	4.93%
Balloon Amount	19,000,000
Face Amount of Mortgages	22,400,000
Carrying Amount December 31, 2013	22,400,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Number of units	297
5% Mortgage Loan Payable Due 2014 [Member] | Residential Real Estate [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate	5.00%
Balloon Amount	28,000,000
Face Amount of Mortgages	28,000,000
Carrying Amount December 31, 2013	28,000,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Note Payable Due 2013 [Member] | Land, Alto Ave [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	1,600,000
Face Amount of Mortgages	1,600,000
Carrying Amount December 31, 2013	1,600,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
Mortgage Note Payable Due 2013 [Member] | Prime Rate [Member] | Land, Alto Ave [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	1.00%
Mortgage Note Payable Due 2013 [Member] | Industrial Land [Member]
Mortgage Loans on Real Estate [Line Items]
Balloon Amount	2,100,000
Face Amount of Mortgages	2,100,000
Carrying Amount December 31, 2013	2,100,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
Mortgage Note Payable Due 2013 [Member] | Prime Rate [Member] | Industrial Land [Member]
Mortgage Loans on Real Estate [Line Items]
Interest Rate, Basis Spread on Variable Rate	1.00%