Mortgage Indebtedness - Additional Information (Detail) - USD ($) | Sep. 30, 2015 | Sep. 17, 2015 | Apr. 13, 2015 | Jan. 27, 2015 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Dec. 31, 2014 |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Secured credit facility borrowing capacity | $ 325,000,000 | | | | | $ 325,000,000 | | $ 30,000,000 | $ 325,000,000 | | $ 30,000,000 | | |
Credit facility withdrawals | | | | | | | | | $ 271,500,000 | | | $ 18,400,000 | |
Mortgage indebtedness, weighted average interest rate | | | | | | | | | 3.60% | | | 3.60% | |
Mortgage indebtedness, outstanding principal | 993,296,000 | | | | | 993,296,000 | | | $ 993,296,000 | | | $ 417,369,000 | |
Cash paid for interest | | | | | | | | | 13,354,000 | | 6,022,000 | | |
Mortgage indebtedness, carrying amount | 602,408,000 | | | | | 602,408,000 | | | $ 602,408,000 | | | $ 400,509,000 | |
Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | | | | | | 2.60% | [1] | | 2.70% | [2] |
Mortgage indebtedness, outstanding principal | 271,500,000 | [1] | | | | 271,500,000 | [1] | | $ 271,500,000 | [1] | | $ 18,392,000 | [2] |
The Huntington National Bank | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Credit facility withdrawals | | | | | | 14,848,000 | | | 14,848,000 | | | | |
Repayment of secured credit facility | | | | | | 14,848,000 | | | 33,240,000 | | | | |
Key Bank Senior Facility | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Secured credit facility borrowing capacity | | | $ 325,000,000 | | | | | | | | | | |
Secured credit facility, remaining borrowing capacity | 53,500,000 | | | | | 53,500,000 | | | 53,500,000 | | | | |
Key Bank Senior Facility | Revolving Line of Credit | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Secured credit facility borrowing capacity | | | $ 125,000,000 | | | | | | | | | | |
Percentage of secured credit facility available for swingline loans | | | 10.00% | | | | | | | | | | |
Percentage of secured credit facility available for issuance of letters of credit | | | 10.00% | | | | | | | | | | |
Key Bank Senior Facility | Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Secured credit facility borrowing capacity | | | $ 200,000,000 | | | | | | | | | | |
Secured credit facility, remaining borrowing capacity | $ 0 | | | | | 0 | | | 0 | | | | |
Key Bank Senior Facility | 1-month LIBOR | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | 2.45% | | | | | | | | | | | | |
Key Bank Senior Facility | Limited Partner | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 3 years | | | | | | | | | | |
Increase in maximum borrowing capacity | | | $ 450,000,000 | | | | | | | | | | |
Secured credit facility, maturity date | | | Sep. 17, 2018 | | | | | | | | | | |
Key Bank Senior Facility | Limited Partner | If greater than or equal to 50% of the revolver is used | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Percentage of fee on line of credit facility outstanding | | | 0.20% | | | | | | | | | | |
Key Bank Senior Facility | Limited Partner | If less than 50% of the revolver is used | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Percentage of fee on line of credit facility outstanding | | | 0.25% | | | | | | | | | | |
Key Bank Interim Facility | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Secured credit facility borrowing capacity | | | $ 120,000,000 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 364 days | | | | | | | | | | |
Secured credit facility, remaining borrowing capacity | $ 0 | | | | | 0 | | | 0 | | | | |
Key Bank Interim Facility | 1-month LIBOR | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | 5.00% | | | | | | | | | | | | |
Key Bank Interim Facility | Limited Partner | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Percentage of net proceeds from equity issuances, sales of assets, refinancing of assets | | | 100.00% | | | | | | | | | | |
Key Bank Interim Facility | Limited Partner | 1-month LIBOR | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 5.00% | | | | | | | | | | |
Key Bank Interim Facility | Limited Partner | Base Rate | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 4.00% | | | | | | | | | | |
Key Bank Interim Facility | Limited Partner | If IROP elects to extend its maturity | 1-month LIBOR | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 6.50% | | | | | | | | | | |
Key Bank Interim Facility | Limited Partner | If IROP elects to extend its maturity | Base Rate | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 5.50% | | | | | | | | | | |
Sponsor | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Cash paid for interest | | | | | | 243,000 | | $ 241,000 | $ 722,000 | | $ 723,000 | | |
Mortgages-Floating Rate | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | | | | | | 2.40% | | | 2.40% | |
Mortgage indebtedness, outstanding principal | $ 38,075,000 | | | | | 38,075,000 | | | $ 38,075,000 | | | $ 38,075,000 | |
Mortgages-Fixed Rate | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | | | | | | 3.80% | | | 3.80% | |
Mortgage indebtedness, outstanding principal | $ 563,721,000 | | | | | $ 563,721,000 | | | $ 563,721,000 | | | $ 360,902,000 | |
Iron Rock Ranch | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | | 3.40% | | | | | | | | |
Mortgage indebtedness, carrying amount | | | | | $ 22,900,000 | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | | | Feb. 1, 2025 | | | | | | | | |
Stonebridge At The Ranch | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | 3.20% | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | | $ 20,527,000 | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | | May 1, 2025 | | | | | | | | | |
Creekstone At R T P | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 3.90% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 23,250,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Jun. 10, 2023 | | | | | | | | | | |
Principal date | | | Jun. 10, 2016 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
Fountains Southend | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 4.30% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 23,750,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Feb. 5, 2024 | | | | | | | | | | |
Principal date | | | Feb. 5, 2017 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
I R T Millenia | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 3.80% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 25,000,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Mar. 5, 2021 | | | | | | | | | | |
Principal date | | | Apr. 5, 2018 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
I R T Millenia | Supplemental Loan Agreement | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 4.30% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 4,175,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Mar. 5, 2021 | | | | | | | | | | |
Principal date | | | May 5, 2018 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
Talison Row | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 4.10% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 33,635,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Sep. 10, 2023 | | | | | | | | | | |
Principal date | | | Sep. 10, 2016 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
Aventine Greenville | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 3.20% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 30,600,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Mar. 5, 2021 | | | | | | | | | | |
Principal date | | | Nov. 4, 2016 | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | 30 years | | | | | | | | | | |
Waterstone at Brier Creek | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 3.70% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 16,250,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Apr. 5, 2022 | | | | | | | | | | |
Waterstone at Brier Creek | Supplemental Loan Agreement | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | 4.20% | | | | | | | | | | |
Mortgage indebtedness, carrying amount | | | $ 4,175,000 | | | | | | | | | | |
Interest payment period | | | | | | | | | Monthly | | | | |
Mortgage indebtedness, maturity date | | | Apr. 5, 2022 | | | | | | | | | | |
Weighted Average | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness, weighted average interest rate | | | | | | | | | 3.70% | | | | |
Mortgage indebtedness maturity (in years) | | | | | | | | | 5 years 1 month 6 days | | | 7 years 1 month 6 days | |
Weighted Average | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | | | | | | | 3 years | [1] | | 1 year 9 months 18 days | [2] |
Weighted Average | Mortgages-Floating Rate | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | | | | | | | 5 years 7 months 6 days | | | 6 years 3 months 18 days | |
Weighted Average | Mortgages-Fixed Rate | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Mortgage indebtedness maturity (in years) | | | | | | | | | 7 years | | | 7 years 6 months | |
Minimum | Key Bank Senior Facility | Limited Partner | 1-month LIBOR | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 1.65% | | | | | | | | | | |
Minimum | Key Bank Senior Facility | Limited Partner | Base Rate | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 0.65% | | | | | | | | | | |
Maximum | Key Bank Senior Facility | Limited Partner | 1-month LIBOR | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 2.45% | | | | | | | | | | |
Maximum | Key Bank Senior Facility | Limited Partner | Base Rate | Secured Credit Facility | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Debt instrument interest rate | | | 1.45% | | | | | | | | | | |
Maximum | Key Bank Interim Facility | Limited Partner | Senior Interim Term Loan | | | | | | | | | | | | | |
Mortgage Loans On Real Estate [Line Items] | | | | | | | | | | | | | |
Principal amount outstanding | | | $ 100,000,000 | | | | | | | | | | |
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[1] | (1) The secured credit facility total capacity is $325.0 million, of which $271.5 million was drawn as of September 30, 2015. |
[2] | The secured credit facility total capacity was $30.0 million, of which $18.4 million was drawn as of December 31, 2014. |