v3.7.0.1

Mortgages and Notes Payable - Summary of Mortgages and Notes Payable (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Line Of Credit Facility [Line Items]
Mortgages and notes payable	$ 883,431	$ 869,524
Mortgages and notes payable, net	67,705	106,686
Secured Debt
Line Of Credit Facility [Line Items]
Mortgages and notes payable	68,431	107,524
Debt issuance costs, net	$ (726)	(838)
M&T Bank | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-12
Maturity Date	2020-04
Interest Rate	1 month LIBOR+1.90%
Mortgages and notes payable		21,335
M&T Bank | 1 Month LIBOR | Secured Debt
Line Of Credit Facility [Line Items]
Basis spread on variable rate	1.90%
Sun Life | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2012-03
Maturity Date	2021-10
Debt instrument, interest rate	5.13%
Mortgages and notes payable	$ 11,855	12,036
Aegon | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2012-04
Maturity Date	2023-10
Debt instrument, interest rate	6.38%
Mortgages and notes payable	$ 9,490	9,804
Legg Mason Mortgage Capital Corporation | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-08
Maturity Date	2022-08
Debt instrument, interest rate	7.06%
Mortgages and notes payable	$ 6,119	6,538
Columbian Mutual Life Insurance Company | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-08
Maturity Date	2025-09
Debt instrument, interest rate	7.00%
Mortgages and notes payable	$ 1,520	1,538
Symetra Financial | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2011-03
Maturity Date	2031-04
Debt instrument, interest rate	6.34%
Mortgages and notes payable	$ 1,022	1,036
Notes holders | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2008-12
Maturity Date	2023-12
Debt instrument, interest rate	6.25%
Mortgages and notes payable	$ 750	750
Standard Insurance Company Due August 2030 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-07
Maturity Date	2030-08
Debt instrument, interest rate	6.75%
Mortgages and notes payable	$ 589	597
Siemens Financial Services, Inc. | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-09
Maturity Date	2020-09
Debt instrument, interest rate	5.47%
Mortgages and notes payable	$ 5,916	6,010
Standard Insurance Company Due May 2034 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2009-04
Maturity Date	2034-05
Debt instrument, interest rate	6.88%
Mortgages and notes payable	$ 1,842	1,870
Wells Fargo Bank, N.A. | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2007-05
Maturity Date	2017-06
Debt instrument, interest rate	6.69%
Mortgages and notes payable		1,694
Standard Insurance Company Due June 2034 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2009-05
Maturity Date	2034-06
Debt instrument, interest rate	6.88%
Mortgages and notes payable	$ 1,322	1,342
Standard Insurance Company Due April 2031 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-03
Maturity Date	2031-04
Debt instrument, interest rate	7.00%
Mortgages and notes payable		1,058
Standard Insurance Company Due April 2031 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-03
Maturity Date	2031-04
Debt instrument, interest rate	7.00%
Mortgages and notes payable		844
Columbus Life Insurance | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2013-02
Maturity Date	2026-01
Debt instrument, interest rate	4.65%
Mortgages and notes payable	$ 9,209	9,400
Athene Annuity And Life Company | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2012-02
Maturity Date	2017-02
Debt instrument, interest rate	3.76%
Mortgages and notes payable		12,701
PNC Bank | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2016-10
Maturity Date	2026-11
Debt instrument, interest rate	3.62%
Mortgages and notes payable	$ 18,797	$ 18,971

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- Definition

Debt instrument issuance date month and year.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(22))
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+ References

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-Publisher FASB
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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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