Discontinued Operations and Held For Sale - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
Aug. 06, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of CBR business		$ 87,076	$ 0	$ 0
Transaction expenses		14,111	0	0
Discontinued Operations, Held-for-sale or Disposed of by Sale \| CBR business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration for sale of wholly-owned subsidiary	$ 519,300
Gain on sale of CBR business	$ 87,100	87,076	0	$ 0
Capital expenditures		1,600	4,900
Depreciation and amortization expense		$ 8,400	$ 21,700

Increase (Decrease) In Transaction Costs

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- Definition

Amount of capital expenditure attributable to discontinued operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

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- Definition

Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Section 50
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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.

+ References

No definition available.

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