The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fixed interest rate related to the interest rate derivative.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

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Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Derivative [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ (2,302)	$ (2,442)	$ 3,508	$ (18,521)
Amount reclassified from accumulated other comprehensive loss	1,034	2,484	2,069	3,909
Interest Expense	35,812	$ 40,375	72,748	$ 77,811
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			3,700
Fair Value, Measurements, Recurring [Member]
Derivative [Line Items]
Interest Rate Cash Flow Hedge Liability at Fair Value	(4,729)		(4,729)		$ (9,291)
Fair Value Inputs Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Derivative [Line Items]
Interest Rate Cash Flow Hedge Liability at Fair Value	(4,729)		(4,729)		(9,291)
Interest Rate Cash Flow Hedge Derivative At Fair Value Net	(4,729)		$ (4,729)		(9,291)
Derivative @ 1.053% 265.000M [Member]
Derivative [Line Items]
Derivative, Inception Date			Aug. 01, 2016
Derivative, Maturity Date			Jan. 05, 2022
Derivative, Notional Amount	$ 265,000		$ 265,000
Derivative, Description of Variable Rate Basis			1 Month LIBOR with Floor
Derivative, Fixed Interest Rate	1.053%		1.053%
Interest Rate Cash Flow Hedge Liability at Fair Value					(2,472)
Derivative @ 1.303% 19.678M [Member]
Derivative [Line Items]
Derivative, Inception Date			Apr. 07, 2016
Derivative, Maturity Date			Apr. 01, 2023
Derivative, Notional Amount	$ 19,219		$ 19,219
Derivative, Description of Variable Rate Basis			1 Month LIBOR
Derivative, Fixed Interest Rate	1.303%		1.303%
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (360)		$ (360)		(494)
Derivative @ 1.490% 32.809M [Member]
Derivative [Line Items]
Derivative, Inception Date			Dec. 01, 2016
Derivative, Maturity Date			Nov. 01, 2023
Derivative, Notional Amount	$ 32,069		$ 32,069
Derivative, Description of Variable Rate Basis			1 Month LIBOR
Derivative, Fixed Interest Rate	1.49%		1.49%
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (851)		$ (851)		(1,181)
Derivative @ 1.542% 24.000M [Member]
Derivative [Line Items]
Derivative, Inception Date			Sep. 17, 2019
Derivative, Maturity Date			Mar. 17, 2025
Derivative, Notional Amount	$ 24,000		$ 24,000
Derivative, Description of Variable Rate Basis			1 Month LIBOR
Derivative, Fixed Interest Rate	1.542%		1.542%
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (812)		$ (812)		(1,288)
Derivative @ 2.366% 37.022M [Member]
Derivative [Line Items]
Derivative, Inception Date			Jun. 02, 2017
Derivative, Maturity Date			Jun. 02, 2027
Derivative, Notional Amount	$ 36,306		$ 36,306
Derivative, Description of Variable Rate Basis			1 Month LIBOR with Floor
Derivative, Fixed Interest Rate	2.366%		2.366%
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (2,706)		$ (2,706)		$ (3,856)