Investments in Partnerships (Schedule of Principal Payments Based On Respective Partnership Interest) (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	$ 24,079
Balloon Payments	177,995
Total	202,074
Property Total	442,330
2014 [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	3,313
Balloon Payments	0
Total	3,313
Property Total	6,675
2015 [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	3,461
Balloon Payments	3,283
Total	6,744
Property Total	15,157
2016 [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	3,591
Balloon Payments	18,232
Total	21,823
Property Total	80,110
2017 [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	3,789
Balloon Payments	0
Total	3,789
Property Total	7,577
2018 [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	3,212
Balloon Payments	58,519
Total	61,731
Property Total	123,462
2019 and Thereafter [Member]
Mortgage Loans on Real Estate [Line Items]
Principal Amortization	6,713
Balloon Payments	97,961
Total	104,674
Property Total	$ 209,349

Mortgage Loans On Partnership Real Estate Carrying Amount Of Mortgages

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Mortgage Loans On Partnership Real Estate Periodic Payment Terms Balloon Payment Amount

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Mortgage Loans On Partnership Real Estate Periodic Payment Terms Principal Amortization

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