Interest Rate Swaps - Summary of Interest Rate Swap Agreements (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Interest Rate Swap $125M Notional Effective February 14, 2018
Derivative [Line Items]
Interest rate swap agreement, effective date	Feb. 14, 2018
Interest rate swap agreement, maturity date	Jan. 14, 2022
Interest Strike Rate	1.349%
Current Notional Value	$ 125,000	$ 125,000
Fair Value	$ (1,955)	489
Interest Rate Swap $100M Notional Effective August 14, 2018
Derivative [Line Items]
Interest rate swap agreement, effective date	Aug. 14, 2018
Interest rate swap agreement, maturity date	Jan. 14, 2022
Interest Strike Rate	1.406%
Current Notional Value	$ 100,000	100,000
Fair Value	$ (1,638)	277
Interest Rate Swap $100M Notional Effective December 14, 2018
Derivative [Line Items]
Interest rate swap agreement, effective date	Dec. 14, 2018
Interest rate swap agreement, maturity date	Aug. 14, 2021
Interest Strike Rate	1.764%
Current Notional Value	$ 100,000	100,000
Fair Value	$ (1,426)	(332)
Interest Rate Swap $150M Notional Effective July 22, 2019
Derivative [Line Items]
Interest rate swap agreement, effective date	Jul. 22, 2019
Interest rate swap agreement, maturity date	Nov. 22, 2024
Interest Strike Rate	2.7625%
Current Notional Value	$ 150,000	150,000
Fair Value	$ (15,850)	$ (8,156)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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

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- Definition

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- Definition

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

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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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