Derivative and Hedging Activities - Schedule of Key Terms and Fair Values of Our Interest Rate Swap Derivatives (Detail)	3 Months Ended
Mar. 31, 2020 USD ($)
Interest Swap Rate at 1.14 % Fixed Rate[Member]
Derivative [Line Items]
Aggregate notional value of interest rate swaps	$ 100,000,000
Forward swaps interest rate	1.41%
Floating Rate Index	One-Month LIBOR
Forward swaps effective date	Mar. 29, 2017
Expiration Date	Sep. 29, 2023
Fair Value	$ (3,734,000)
Interest Swap Rate at 2.71 % Fixed Rate[Member]
Derivative [Line Items]
Aggregate notional value of interest rate swaps	$ 150,000,000
Forward swaps interest rate	2.71%
Floating Rate Index	One-Month LIBOR
Forward swaps effective date	Dec. 13, 2018
Expiration Date	Jun. 19, 2023
Fair Value	$ (11,408,000)

Derivative floating rate index.

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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