Goodwill and Other Intangible Assets and Liabilities - Summary of Goodwill, Indefinite-Lived Intangibles and Amortizable Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Intangible Assets By Major Class [Line Items]
Goodwill, Gross	$ 788,107	$ 788,107
Goodwill, Net	788,107	788,107
Total Amortizable intangible assets, Gross	900,700	900,700
Total Amortizable intangible assets, Accumulated Amortization	(224,053)	(165,651)
Total Amortizable intangible assets, Net	676,647	735,049
Intangible assets including goodwill, Gross	2,561,127	2,561,127
Intangible assets including goodwill, Accumulated Amortization	(224,053)	(165,651)
Intangible assets including goodwill, Net	2,337,074	2,395,476
Customer Relationships
Intangible Assets By Major Class [Line Items]
Total Amortizable intangible assets, Gross	814,240	814,240
Total Amortizable intangible assets, Accumulated Amortization	(189,090)	(140,788)
Total Amortizable intangible assets, Net	625,150	673,452
Acquired Software
Intangible Assets By Major Class [Line Items]
Total Amortizable intangible assets, Gross	71,700	71,700
Total Amortizable intangible assets, Accumulated Amortization	(31,069)	(22,798)
Total Amortizable intangible assets, Net	40,631	48,902
Trade Name
Intangible Assets By Major Class [Line Items]
Total Amortizable intangible assets, Gross	9,800	9,800
Total Amortizable intangible assets, Accumulated Amortization	(953)	(340)
Total Amortizable intangible assets, Net	8,847	9,460
Non-compete Agreements
Intangible Assets By Major Class [Line Items]
Total Amortizable intangible assets, Gross	2,860	2,860
Total Amortizable intangible assets, Accumulated Amortization	(1,716)	(1,287)
Total Amortizable intangible assets, Net	1,144	1,573
Content Library
Intangible Assets By Major Class [Line Items]
Total Amortizable intangible assets, Gross	2,100	2,100
Total Amortizable intangible assets, Accumulated Amortization	(1,225)	(438)
Total Amortizable intangible assets, Net	875	1,662
Trade Name
Intangible Assets By Major Class [Line Items]
Indefinite-lived intangibles, Gross	872,320	872,320
Indefinite-lived intangibles, Net	$ 872,320	$ 872,320

Indefinite lived intangible assets excluding goodwill gross.

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Intangible assets accumulated amortization.

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Intangible Assets Gross Including Goodwill

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

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

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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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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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