Discontinued Operations - Summary of Financial Results for MBP Titan (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations		$ (66,748)	$ (153,582)	$ (134,219)
Impairment of goodwill	$ 178	9,635	87,862	0
MBP Titan \| Discontinued Operations, Disposed of by Means Other than Sale, Abandonment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating expenses		40,692	37,423	33,830
Operating income (loss)		(40,692)	(37,423)	(33,830)
Income (loss) before income taxes		(40,692)	(37,423)	(33,830)
Income (loss) from discontinued operations		(40,692)	(37,423)	(33,830)
Impairment of goodwill		9,635	0	0
Impairment of other noncurrent assets		$ 12,406	$ 0	$ 0

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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