Intangible Assets and Liabilities Estimated Future Annual Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Intangible Assets [Abstract]
2021 (amount remaining at March 31, 2021)	$ 28,447
2022	27,516
2023	19,898
2024	15,700
2025	14,706
Thereafter	16,594
Total intangible assets subject to amortization (accretion)	122,861
2021 (amount remaining at March 31, 2021)	(1,472)
2022	(459)
2023	0
2024	0
2025	0
Thereafter	0
Intangible liabilities, Net	(1,931)	$ (2,421)
2021 (amount remaining at March 31, 2021)	26,975
2022	27,057
2023	19,898
2024	15,700
2025	14,706
Thereafter	16,594
Total intangible assets (liabilities), net	$ 120,930

Finite-Lived Intangible Asset, Expected Amortization, after Year Four

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- Definition

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

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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 Four

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- Definition

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

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- Definition

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, after Year Four

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- Definition

Finite-Lived Intangible Liabilities, Accretion, Remainder of Fiscal Year

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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, Net

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Finite-Lived Intangible Liabilities, Year Four

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- Definition

The line item is inclusive of finite-lived and indefinite-lived intangible assets.

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- Definition

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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

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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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
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