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Mortgage Notes Payable, Revolving Credit Facility, and Term Loan Facility Narrative (Detail) |  | 12 Months Ended
--- | --- | ---
Oct. 27, 2017 | Dec. 31, 2017 property mortgage
Debt Instrument [Line Items] |  |
Weighted average interest rate on debt outstanding (as percent) |  | 4.42%
Encumbered properties |  | 96
Revolving Credit Facility |  |
Debt Instrument [Line Items] |  |
Encumbered properties |  | 29
Fixed rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Weighted average interest rate on debt outstanding (as percent) |  | 6.25%
Encumbered properties |  | 48
Mortgage Notes Payable |  |
Debt Instrument [Line Items] |  |
Number of mortgage notes payable | mortgage |  | 45
Maturity date of mortgage notes payable, start date |  | Jul. 01, 2018
Maturity date of mortgage notes payable, end date |  | Jul. 01, 2045
Weighted average interest rate on debt outstanding (as percent) |  | 4.56%
Encumbered properties |  | 67
Variable rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Encumbered properties |  | 19
Variable rate Line of Credit | Revolving Credit Facility |  |
Debt Instrument [Line Items] |  |
Libor rate (as percent) |  | 1.75%
Encumbered properties |  | 29
New Fixed Rate Mortgage Notes Payable |  |
Debt Instrument [Line Items] |  |
Weighted average interest rate on debt outstanding (as percent) |  | 3.78%
Minimum | Fixed rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Debt instrument, interest rate, stated percentage |  | 3.55%
Minimum | Variable rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Libor rate (as percent) |  | 2.15%
Maximum | Fixed rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Debt instrument, interest rate, stated percentage |  | 6.63%
Maximum | Variable rate mortgage loans |  |
Debt Instrument [Line Items] |  |
Libor rate (as percent) |  | 2.75%
London Interbank Offered Rate (LIBOR) |  |
Debt Instrument [Line Items] |  |
Libor rate (as percent) | 2.75% | 1.56%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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