v3.8.0.1

Mortgages and Notes Payable - Summary of Mortgages and Notes Payable (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Line Of Credit Facility [Line Items]
Mortgages and notes payable	$ 1,181,470	$ 869,524
Mortgages and notes payable, net	67,832	106,686
Secured Debt
Line Of Credit Facility [Line Items]
Mortgages and notes payable	68,470	107,524
Debt issuance costs, net	$ (638)	(838)
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	$ 18,622	18,971
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	$ 11,670	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	$ 9,168	9,804
Symetra Financial | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2017-11
Maturity Date	2026-10
Debt instrument, interest rate	3.65%
Mortgages and notes payable	$ 6,685
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	$ 5,820	6,010
Legg Mason Mortgage Capital | 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	$ 5,670	6,538
M&T Bank | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2017-10
Maturity Date	2021-08
Interest Rate	1 month LIBOR+3%
Mortgages and notes payable	$ 5,183
M&T Bank | 1 Month LIBOR | Secured Debt
Line Of Credit Facility [Line Items]
Basis spread on variable rate	3.00%
Standard Insurance Company Due May 2034 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2009-04
Maturity Date	1934-05
Debt instrument, interest rate	6.88%
Mortgages and notes payable	$ 1,813	1,870
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	$ 1,500	1,538
Symetra Financial Due April 2031 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2011-03
Maturity Date	1931-04
Debt instrument, interest rate	6.34%
Mortgages and notes payable	$ 1,008	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	$ 581	597
M and T Bank Due April 2020 | 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 and T Bank Due April 2020 | 1 Month LIBOR | Secured Debt
Line Of Credit Facility [Line Items]
Basis spread on variable rate	1.90%
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	1934-06
Debt instrument, interest rate	6.88%
Mortgages and notes payable		1,342
Standard Insurance Company Due April 2031 | Secured Debt
Line Of Credit Facility [Line Items]
Origination Date	2010-03
Maturity Date	1931-04
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	1931-04
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		9,400
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

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+ References

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-Name Accounting Standards Codification
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-SubTopic 10
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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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