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Mortgage Notes Payable, Revolving Credit Facility, Interest Expense and Amortization of Deferred Debt Costs - Summary of Notes Payable (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 880,271 | $ 897,888
Interest rate | 4.40% | 3.90%
Variable rate debt | $ 74,591 | $ 0
Scheduled maturity period | 7 years 11 months 14 days |
Total notes payable | $ 1,032,189 | 965,528
Interest rate during period | 5.02% |
Fixed rate mortgage notes payable |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 910,189 | 890,393
Interest rate | 5.18% |
Scheduled maturity period | 8 years 6 months 10 days |
Fixed rate mortgage notes payable | 5.88% due January 2019 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 0 | 30,201
Interest rate | 5.88% |
Fixed rate mortgage notes payable | 5.76% due May 2019 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 9,159 | 9,783
Interest rate | 5.76% |
Fixed rate mortgage notes payable | 5.62% due July 2019 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 12,676 | 13,529
Interest rate | 5.62% |
Fixed rate mortgage notes payable | 5.79% due September 2019 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 12,714 | 13,543
Interest rate | 5.79% |
Fixed rate mortgage notes payable | 5.22% due January 2020 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 11,295 | 12,029
Interest rate | 5.22% |
Fixed rate mortgage notes payable | 5.60% due May 2020 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 9,601 | 9,948
Interest rate | 5.60% |
Fixed rate mortgage notes payable | 5.30% due June 2020 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 7,766 | 8,244
Interest rate | 5.30% |
Fixed rate mortgage notes payable | 5.83% due July 2020 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 36,711 | 37,998
Interest rate | 5.83% |
Fixed rate mortgage notes payable | 5.81% due February 2021 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 6,943 | 7,325
Interest rate | 5.81% |
Fixed rate mortgage notes payable | 6.01% due August 2021 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 5,480 | 5,649
Interest rate | 6.01% |
Fixed rate mortgage notes payable | 5.62% due June 2022 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 31,723 | 32,673
Interest rate | 5.62% |
Fixed rate mortgage notes payable | 6.08% due September 2022 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 9,728 | 9,999
Interest rate | 6.08% |
Fixed rate mortgage notes payable | 6.43% due April 2023 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 10,609 | 10,877
Interest rate | 6.43% |
Fixed rate mortgage notes payable | 6.28% due February 2024 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 11,702 | 12,577
Interest rate | 6.28% |
Fixed rate mortgage notes payable | 7.35% due June 2024 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 14,952 | 15,452
Interest rate | 7.35% |
Fixed rate mortgage notes payable | 7.60% due June 2024 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 13,013 | 13,438
Interest rate | 7.60% |
Fixed rate mortgage notes payable | 7.02% due July 2024 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 23,198 | 23,873
Interest rate | 7.02% |
Fixed rate mortgage notes payable | 7.45% due July 2024 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 27,222 | 28,115
Interest rate | 7.45% |
Fixed rate mortgage notes payable | 7.30% due January 2025 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 27,168 | 28,025
Interest rate | 7.30% |
Fixed rate mortgage notes payable | 6.18% due January 2026 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 14,086 | 14,537
Interest rate | 6.18% |
Fixed rate mortgage notes payable | 5.31% due April 2026 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 102,310 | 105,817
Interest rate | 5.31% |
Fixed rate mortgage notes payable | 4.30% due October 2026 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 30,888 | 32,016
Interest rate | 4.30% |
Fixed rate mortgage notes payable | 4.53% due November 2026 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 35,258 | 36,507
Interest rate | 4.53% |
Fixed rate mortgage notes payable | 4.70% due December 2026 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 16,515 | 17,086
Interest rate | 4.70% |
Fixed rate mortgage notes payable | 5.84% due May 2027 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 62,630 | 64,472
Interest rate | 5.84% |
Fixed rate mortgage notes payable | 4.04% due April 2028 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 15,345 | 15,859
Interest rate | 4.04% |
Fixed rate mortgage notes payable | 3.51% due June 2028 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 38,120 | 39,968
Interest rate | 3.51% |
Fixed rate mortgage notes payable | 3.99% due September 2028 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 15,547 | 16,055
Interest rate | 3.99% |
Fixed rate mortgage notes payable | 3.69% Due March 2030 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 27,060 | 27,884
Interest rate | 3.69% |
Fixed rate mortgage notes payable | 3.99% Due April 2030 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 14,526 | 14,950
Interest rate | 3.99% |
Fixed rate mortgage notes payable | 3.39% due January 2032 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 38,076 | 39,140
Interest rate | 3.39% |
Fixed rate mortgage notes payable | 4.88% due September 2032 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 69,691 | 71,211
Interest rate | 4.88% |
Fixed rate mortgage notes payable | 3.75% due December 2032 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 58,523 | 60,000
Interest rate | 3.75% |
Fixed rate mortgage notes payable | 4.41% mortgage maturing 2033 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 31,941 | 0
Interest rate | 4.41% |
Fixed rate mortgage notes payable | 4.69% fixed rate loan maturing in 2034 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 22,900 | 0
Interest rate | 4.69% |
Fixed rate mortgage notes payable | 8.00% due April 2034 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 11,781 | 11,613
Interest rate | 8.00% |
Fixed rate mortgage notes payable | 4.67% Construction To Permanent Loan Due 2035 |  |
Notes Payable [Line Items] |  |
Fixed rate mortgages | $ 23,332 | 0
Interest rate | 4.67% |
Variable rate loans payable |  |
Notes Payable [Line Items] |  |
Variable rate debt | $ 122,000 | 75,135
Interest rate spread on LIBOR | 3.84% |
Scheduled maturity period | 3 years 8 months 8 days |
Variable rate loans payable | Metro Pike Center Bank Loan |  |
Notes Payable [Line Items] |  |
Variable rate debt | $ 0 | 14,135
Interest rate spread on LIBOR | 1.65% |
Revolving Credit Facility | New Facility | Line of Credit |  |
Notes Payable [Line Items] |  |
Variable rate debt | $ 47,000 | 61,000
Interest rate spread on LIBOR | 1.35% |
Revolving Credit Facility | New Facility | Term Facility |  |
Notes Payable [Line Items] |  |
Interest rate spread on LIBOR | 1.30% |
Term Facility | New Facility | Line of Credit |  |
Notes Payable [Line Items] |  |
Variable rate debt | $ 75,000 | $ 0
Interest rate spread on LIBOR | 1.30% |

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