v3.20.2

Interest Rate Swaps - Summary of Interest-rate Swap Agreements (Detail) - Interest Rate Swap - USD ($)	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Fair Value	$ (85,678,000)	$ (21,560,000)
Bank of America
Derivative [Line Items]
Derivative, Maturity date	Nov. 30, 2023
Derivative, Fixed rate	2.80%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,194,000)	(1,136,000)
Bank of Montreal One
Derivative [Line Items]
Derivative, Maturity date	Jul. 31, 2024
Derivative, Fixed rate	1.16%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 40,000,000
Fair Value	$ (1,635,000)	740,000
Bank of Montreal Two
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2025
Derivative, Fixed rate	1.91%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (1,988,000)	(402,000)
Bank of Montreal Three
Derivative [Line Items]
Derivative, Maturity date	Jul. 31, 2025
Derivative, Fixed rate	2.32%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,688,000)	(970,000)
Bank of Montreal Four
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2026
Derivative, Fixed rate	1.92%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,346,000)	(448,000)
Bank of Montreal Five
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2026
Derivative, Fixed rate	2.05%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 40,000,000
Fair Value	$ (4,040,000)	(1,014,000)
Bank of Montreal Six
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2026
Derivative, Fixed rate	2.33%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 10,000,000
Fair Value	$ (1,328,000)	(460,000)
Bank of Montreal Seven
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2026
Derivative, Fixed rate	1.99%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,760,000)	(577,000)
Bank of Montreal Eight
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2027
Derivative, Fixed rate	2.37%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,760,000)	(1,306,000)
Bank of Montreal Nine
Derivative [Line Items]
Derivative, Maturity date	May 31, 2029
Derivative, Fixed rate	2.09%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,633,000)	(799,000)
Capital One, National Association One
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2021
Derivative, Fixed rate	1.05%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 15,000,000
Fair Value	$ (213,000)	143,000
Capital One, National Association Two
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2024
Derivative, Fixed rate	1.58%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 15,000,000
Fair Value	$ (935,000)	10,000
Capital One, National Association Three
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2026
Derivative, Fixed rate	2.08%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 35,000,000
Fair Value	$ (3,549,000)	(911,000)
Capital One, National Association Four
Derivative [Line Items]
Derivative, Maturity date	Apr. 30, 2026
Derivative, Fixed rate	2.68%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 15,000,000
Fair Value	$ (2,102,000)	(944,000)
Capital One, National Association Five
Derivative [Line Items]
Derivative, Maturity date	Jul. 31, 2026
Derivative, Fixed rate	1.32%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 35,000,000
Fair Value	$ (2,182,000)	720,000
Capital One, National Association Six
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2027
Derivative, Fixed rate	2.37%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,738,000)	(1,278,000)
M&T Bank
Derivative [Line Items]
Derivative, Maturity date	Aug. 31, 2021
Derivative, Fixed rate	1.02%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 4,841,000	4,912,000
Fair Value	$ (46,000)	41,000
M&T Bank One
Derivative [Line Items]
Derivative, Maturity date	Sep. 30, 2022
Derivative, Fixed rate	2.83%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (1,490,000)	(862,000)
M&T Bank Two
Derivative [Line Items]
Derivative, Maturity date	Nov. 30, 2023
Derivative, Fixed rate	2.65%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,125,000)	(1,038,000)
Regions Bank
Derivative [Line Items]
Derivative, Maturity date	May 31, 2020
Derivative, Fixed rate	2.12%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 50,000,000
Fair Value		(104,000)
Regions Bank One
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2023
Derivative, Fixed rate	1.18%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (962,000)	376,000
Regions Bank Two
Derivative [Line Items]
Derivative, Maturity date	May 31, 2029
Derivative, Fixed rate	2.11%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,753,000)	(827,000)
Regions Bank Three
Derivative [Line Items]
Derivative, Maturity date	Jun. 30, 2029
Derivative, Fixed rate	2.03%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,579,000)	(651,000)
Truist Financial Corporation One
Derivative [Line Items]
Derivative, Maturity date	Apr. 30, 2024
Derivative, Fixed rate	1.99%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (1,749,000)	(451,000)
Truist Financial Corporation Two
Derivative [Line Items]
Derivative, Maturity date	Apr. 30, 2025
Derivative, Fixed rate	2.20%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,403,000)	(781,000)
Truist Financial Corporation Three
Derivative [Line Items]
Derivative, Maturity date	Jul. 31, 2025
Derivative, Fixed rate	1.99%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,244,000)	(524,000)
Truist Financial Corporation Four
Derivative [Line Items]
Derivative, Maturity date	Dec. 31, 2025
Derivative, Fixed rate	2.30%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,848,000)	(993,000)
Truist Financial Corporation Five
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2026
Derivative, Fixed rate	1.93%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,339,000)	(458,000)
U.S. Bank National Association
Derivative [Line Items]
Derivative, Maturity date	Jun. 30, 2029
Derivative, Fixed rate	2.03%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (3,553,000)	(681,000)
U S Bank National Association One
Derivative [Line Items]
Derivative, Maturity date	Aug. 31, 2029
Derivative, Fixed rate	1.35%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (2,021,000)	881,000
Wells Fargo Bank One
Derivative [Line Items]
Derivative, Maturity date	Feb. 28, 2021
Derivative, Fixed rate	2.39%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 35,000,000
Fair Value	$ (466,000)	(302,000)
Wells Fargo Bank Two
Derivative [Line Items]
Derivative, Maturity date	Oct. 31, 2024
Derivative, Fixed rate	2.72%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 15,000,000
Fair Value	$ (1,642,000)	(795,000)
Wells Fargo Bank Three
Derivative [Line Items]
Derivative, Maturity date	Apr. 30, 2027
Derivative, Fixed rate	2.72%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 25,000,000
Fair Value	$ (4,075,000)	(1,845,000)
Wells Fargo Bank Four
Derivative [Line Items]
Derivative, Maturity date	Jan. 31, 2028
Derivative, Fixed rate	2.37%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 75,000,000
Fair Value	$ (11,292,000)	$ (3,914,000)

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