DEBT - Summary of Debt (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Weighted-average effective interest rate	2.79%	3.19%
Total principal amount	$ 878,000	$ 824,000
Less unamortized debt issuance costs	(1,431)	(3,116)
Total debt, net	876,569	820,884
Gross book value of properties encumbered by debt	$ 1,154,412	1,147,963
Weighted-average remaining term	2 years 6 months
Interest Rate Swap
Debt Instrument [Line Items]
Notional Amount	$ 593,749	$ 595,626
Line of Credit
Debt Instrument [Line Items]
Weighted-average effective interest rate	2.91%	3.38%
Debt instrument, principal amount outstanding	$ 378,000	$ 324,000
Line of Credit \| LIBOR \| Maximum
Debt Instrument [Line Items]
Interest rate margin	2.30%
Line of Credit \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate margin	1.40%
Line of Credit \| Based On Alternative Base Rate \| Maximum
Debt Instrument [Line Items]
Interest rate margin	1.30%
Line of Credit \| Based On Alternative Base Rate \| Minimum
Debt Instrument [Line Items]
Interest rate margin	0.40%
Line of Credit \| Fixed Interest Rate \| Interest Rate Swap
Debt Instrument [Line Items]
Notional Amount	$ 150,000
Term Loan Due January 2021
Debt Instrument [Line Items]
Weighted-average effective interest rate	2.50%	2.65%
Debt instrument, principal amount outstanding	$ 350,000	$ 350,000
Term Loan Due January 2021 \| LIBOR \| Maximum
Debt Instrument [Line Items]
Interest rate margin	2.20%
Term Loan Due January 2021 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate margin	1.35%
Term Loan Due January 2021 \| Based On Alternative Base Rate \| Maximum
Debt Instrument [Line Items]
Interest rate margin	1.20%
Term Loan Due January 2021 \| Based On Alternative Base Rate \| Minimum
Debt Instrument [Line Items]
Interest rate margin	0.35%
Term Loan Due May 2022
Debt Instrument [Line Items]
Weighted-average effective interest rate	3.16%	4.05%
Debt instrument, principal amount outstanding	$ 150,000	$ 150,000
Term Loan Due May 2022 \| LIBOR \| Maximum
Debt Instrument [Line Items]
Interest rate margin	2.15%
Term Loan Due May 2022 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate margin	1.30%
Term Loan Due May 2022 \| Based On Alternative Base Rate \| Maximum
Debt Instrument [Line Items]
Interest rate margin	1.15%
Term Loan Due May 2022 \| Based On Alternative Base Rate \| Minimum
Debt Instrument [Line Items]
Interest rate margin	0.30%
Fixed-Rate Mortgage Notes
Debt Instrument [Line Items]
Weighted-average effective interest rate	3.36%	3.36%
Debt instrument, principal amount outstanding	$ 716,470	$ 717,940
Fixed-Rate Mortgage Notes \| Maximum
Debt Instrument [Line Items]
Interest rate	3.65%
Fixed-Rate Mortgage Notes \| Minimum
Debt Instrument [Line Items]
Interest rate	2.94%
Variable-Rate Mortgage Note \| Fixed Interest Rate \| Interest Rate Swap
Debt Instrument [Line Items]
Notional Amount	$ 93,700	$ 95,600
Long-Term Debt Including Assets Held-For-Sale [Member]
Debt Instrument [Line Items]
Weighted-average effective interest rate	3.04%	3.27%
Debt instrument, principal amount outstanding	$ 1,593,039	$ 1,538,824

The gross book value of real estate properties encumbered by debt as of the period end date.

No definition available.

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- Definition

Weighted Average Maturity Of Debt Investments

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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-Publisher FASB
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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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