Derivative Financial Instruments - Derivative Instruments Recorded at Fair Value (Details) - Interest Rate Swap - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative Financial Instruments
Derivative Assets	$ 1,462	$ 1,925
Derivative Liabilities	(30,791)	(3,455)
Derivatives Designated as Cash Flow Hedges
Derivative Financial Instruments
Derivative Assets - Current		485
Derivative Assets - Noncurrent		1,440
Derivative Liabilities - Current	(5,251)	(788)
Derivative Liabilities - Noncurrent	(11,633)	$ (2,667)
Derivatives Not Designated as Hedging Instruments
Derivative Financial Instruments
Derivative Assets - Current	877
Derivative Assets - Noncurrent	585
Derivative Liabilities - Current	(4,875)
Derivative Liabilities - Noncurrent	$ (9,032)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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