Goodwill and Intangible Assets - Summary of Changes in Carrying Amount of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 53,865		$ 77,170
Accumulated Amortization	(20,235)		(20,235)
Amortization	(1,899)	$ (8,400)
Impairment			(23,305)
Intangibles, net	$ 31,731		$ 33,630
Weighted Average Amortization Period	5 years		5 years
Stream Migration Rights [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 2,328		$ 4,170
Accumulated Amortization	(971)		(971)
Amortization	(20)
Impairment			(1,842)
Intangibles, net	$ 1,337		$ 1,357
Weighted Average Amortization Period	17 years		17 years
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 51,537		$ 73,000
Accumulated Amortization	(19,264)		(19,264)
Amortization	(1,879)
Impairment			(21,463)
Intangibles, net	$ 30,394		$ 32,273
Weighted Average Amortization Period	4 years		4 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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