Intangible Assets and Liabilities - Estimated Future Annual Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Intangible Assets, Net (Excluding Goodwill) [Abstract]
2021 Amortization	$ 38,033
2021 Accretion	(1,962)
2021 Amortization, net	36,071
2022 Amortization	27,599
2022 Accretion	(459)
2022 Amortization, net	27,140
2023 Amortization	19,955
2023 Accretion	0
2023 Amortization, net	19,955
2024 Amortization	15,746
2024 Accretion	0
2024 Amortization, net	15,746
2025 Amortization	14,742
2025 Accretion	0
2025 Amortization, net	14,742
Beyond 2025 Amortization	16,880
Beyond 2025 Accretion	0
Beyond 2025 Amortization, net	16,880
Total intangible assets subject to amortization (accretion)	132,955	$ 185,097
Finite-lived intangible liabilities, net	(2,421)	$ (10,450)
Finite-lived intangible assets (liabilities), net	$ 130,534

Finite-Lived Intangible Assets, Amortization Expense, Net, After Year Five

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Finite-Lived Intangible Assets, Amortization Expense, Net, Year Five

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Finite-Lived Intangible Assets, Amortization Expense, Net, Year Four

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Finite-Lived Intangible Assets, Amortization Expense, Net, Year One

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Finite-Lived Intangible Assets, Amortization Expense, Net, Year Three

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Finite-Lived Intangible Assets, Amortization Expense, Net, Year Two

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Finite-Lived Intangible Assets (Liabilities), Net

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Finite-Lived Intangible Liabilities, Accretion, Year Five

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Finite-Lived Intangible Liabilities, Accretion, Year One

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Finite-Lived Intangible Liabilities, Accretion, Year Three

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Finite-Lived Intangible Liabilities, Accretion, Year Two

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Finite-Lived Intangible Liabilities, Accretion, after Year Five

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Finite-Lived Intangible Liabilities, Year Four

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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