v3.21.2

Interest Rate Swaps - Summary of Interest-rate Swap Agreements (Detail) - Interest Rate Swap - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative, Fixed rate	2.11%
Variable Rate Index	one-month LIBOR
Notional Amount	$ 640,000	$ 859,768
Fair Value	$ (36,196)	(72,103)
Wells Fargo Bank One
Derivative [Line Items]
Derivative, Maturity date	2021-02
Derivative, Fixed rate	2.39%
Notional Amount	$ 0	35,000
Fair Value	$ 0	(70)
M&T Bank
Derivative [Line Items]
Derivative, Maturity date	2021-08
Derivative, Fixed rate	1.02%
Notional Amount	$ 0	4,768
Fair Value	$ 0	(25)
Capital One, National Association One
Derivative [Line Items]
Derivative, Maturity date	2021-12
Derivative, Fixed rate	1.05%
Notional Amount	$ 0	15,000
Fair Value	$ 0	(141)
M&T Bank One
Derivative [Line Items]
Derivative, Maturity date	2022-09
Derivative, Fixed rate	2.83%
Notional Amount	$ 0	25,000
Fair Value	$ 0	(1,139)
Bank of America
Derivative [Line Items]
Derivative, Maturity date	2023-11
Derivative, Fixed rate	2.80%
Notional Amount	$ 0	25,000
Fair Value	$ 0	(1,848)
M&T Bank Two
Derivative [Line Items]
Derivative, Maturity date	2023-11
Derivative, Fixed rate	2.65%
Notional Amount	$ 0	25,000
Fair Value	$ 0	(1,785)
Regions Bank
Derivative [Line Items]
Derivative, Maturity date	2023-12
Derivative, Fixed rate	1.18%
Notional Amount	$ 0	25,000
Fair Value	$ 0	(763)
Truist Financial Corporation One
Derivative [Line Items]
Derivative, Maturity date	2024-04
Derivative, Fixed rate	1.99%
Notional Amount	$ 0	25,000
Fair Value	$ 0	(1,487)
Bank of Montreal One
Derivative [Line Items]
Derivative, Maturity date	2024-07
Derivative, Fixed rate	1.16%
Notional Amount	$ 0	40,000
Fair Value	$ 0	(1,380)
Wells Fargo Bank Two
Derivative [Line Items]
Derivative, Maturity date	2024-10
Derivative, Fixed rate	2.72%
Notional Amount	$ 15,000	15,000
Fair Value	$ (964)	(1,422)
Capital One, National Association Two
Derivative [Line Items]
Derivative, Maturity date	2024-12
Derivative, Fixed rate	1.58%
Notional Amount	$ 15,000	15,000
Fair Value	$ (463)	(799)
Bank of Montreal Two
Derivative [Line Items]
Derivative, Maturity date	2025-01
Derivative, Fixed rate	1.91%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,044)	(1,725)
Truist Financial Corporation Two
Derivative [Line Items]
Derivative, Maturity date	2025-04
Derivative, Fixed rate	2.20%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,324)	(2,084)
Bank of Montreal Three
Derivative [Line Items]
Derivative, Maturity date	2025-07
Derivative, Fixed rate	2.32%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,478)	(2,351)
Truist Financial Corporation Three
Derivative [Line Items]
Derivative, Maturity date	2025-07
Derivative, Fixed rate	1.99%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,174)	(1,941)
Truist Financial Corporation Four
Derivative [Line Items]
Derivative, Maturity date	2025-12
Derivative, Fixed rate	2.30%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,546)	(2,481)
Bank of Montreal Four
Derivative [Line Items]
Derivative, Maturity date	2026-01
Derivative, Fixed rate	1.92%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,156)	(2,039)
Bank of Montreal Five
Derivative [Line Items]
Derivative, Maturity date	2026-01
Derivative, Fixed rate	2.05%
Notional Amount	$ 40,000	40,000
Fair Value	$ (2,062)	(3,523)
Capital One, National Association Three
Derivative [Line Items]
Derivative, Maturity date	2026-01
Derivative, Fixed rate	2.08%
Notional Amount	$ 35,000	35,000
Fair Value	$ (1,842)	(3,078)
Truist Financial Corporation Five
Derivative [Line Items]
Derivative, Maturity date	2026-01
Derivative, Fixed rate	1.93%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,164)	(2,019)
Capital One, National Association Four
Derivative [Line Items]
Derivative, Maturity date	2026-04
Derivative, Fixed rate	2.68%
Notional Amount	$ 15,000	15,000
Fair Value	$ (1,204)	(1,843)
Capital One, National Association Five
Derivative [Line Items]
Derivative, Maturity date	2026-07
Derivative, Fixed rate	1.32%
Notional Amount	$ 35,000	35,000
Fair Value	$ (682)	(1,806)
Bank of Montreal Six
Derivative [Line Items]
Derivative, Maturity date	2026-12
Derivative, Fixed rate	2.33%
Notional Amount	$ 10,000	10,000
Fair Value	$ (692)	(1,156)
Bank of Montreal Seven
Derivative [Line Items]
Derivative, Maturity date	2026-12
Derivative, Fixed rate	1.99%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,300)	(2,372)
Wells Fargo Bank Three
Derivative [Line Items]
Derivative, Maturity date	2027-04
Derivative, Fixed rate	2.72%
Notional Amount	$ 25,000	25,000
Fair Value	$ (2,287)	(3,555)
Bank of Montreal Eight
Derivative [Line Items]
Derivative, Maturity date	2027-12
Derivative, Fixed rate	2.37%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,904)	(3,234)
Capital One, National Association Six
Derivative [Line Items]
Derivative, Maturity date	2027-12
Derivative, Fixed rate	2.37%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,909)	(3,199)
Wells Fargo Bank Four
Derivative [Line Items]
Derivative, Maturity date	2028-01
Derivative, Fixed rate	2.37%
Notional Amount	$ 75,000	75,000
Fair Value	$ (5,743)	(9,650)
Bank of Montreal Nine
Derivative [Line Items]
Derivative, Maturity date	2029-05
Derivative, Fixed rate	2.09%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,557)	(2,994)
Regions Bank One
Derivative [Line Items]
Derivative, Maturity date	2029-05
Derivative, Fixed rate	2.11%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,599)	(3,004)
Regions Bank Two
Derivative [Line Items]
Derivative, Maturity date	2029-06
Derivative, Fixed rate	2.03%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,459)	(2,843)
U.S. Bank National Association
Derivative [Line Items]
Derivative, Maturity date	2029-06
Derivative, Fixed rate	2.03%
Notional Amount	$ 25,000	25,000
Fair Value	$ (1,456)	(2,902)
U S Bank National Association One
Derivative [Line Items]
Derivative, Maturity date	2029-08
Derivative, Fixed rate	1.35%
Notional Amount	$ 25,000	25,000
Fair Value	$ (187)	$ (1,445)

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