Intangible Assets and Liabilities - Estimated Future Annual Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Intangible Assets, Net (Excluding Goodwill) [Abstract]
2020 Amortization	$ 53,028
2020 Accretion	(8,028)
2020 Amortization, net	45,000
2021 Amortization	37,705
2021 Accretion	(1,963)
2021 Amortization, net	35,742
2022 Amortization	27,346
2022 Accretion	(459)
2022 Amortization, net	26,887
2023 Amortization	19,785
2023 Accretion	0
2023 Amortization, net	19,785
2024 Amortization	15,612
2024 Accretion	0
2024 Amortization, net	15,612
Beyond 2024 Amortization	31,621
Beyond 2024 Accretion	0
Beyond 2024 Amortization, net	31,621
Total intangible assets subject to amortization	185,097	$ 257,583
Finite-lived intangible liabilities, net	(10,450)	$ (18,683)
Finite-lived intangible assets (liabilities), net	$ 174,647

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

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Finite-Lived Intangible Assets, Amortization Expense, Net, Remainder of Fiscal Year

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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 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, Remainder of Fiscal Year

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Finite-Lived Intangible Liabilities, Accretion, Year Five

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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, Net

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Finite-Lived Intangible Liabilities, Year Four

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Paragraph 2
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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://fasb.org/us-gaap/role/ref/legacyRef
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