Commitments and Contingencies (Narrative) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Guarantor Obligations [Line Items]
Total lease payments for the duration of the guarantee	$ 19,700
Accrued lease guarantee	10,700	$ 10,700
Noden [Member] \| Next twelve months [Member]
Guarantor Obligations [Line Items]
Purchase Obligation	43,100
Noden [Member] \| Next twenty-four months [Member] [Member]
Guarantor Obligations [Line Items]
Purchase Obligation	$ 55,700

Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for contractual rent under lease arrangements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

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