Net Loss per Share - Additional Information (Detail) - $ / shares shares in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Line Items]
Exchange price	$ 28.66
Exchangeable Senior Notes [Member]
Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share	14.0
Interest rate	2.50%
Exchange price	$ 28.66
Equity Awards [Member]
Earnings Per Share [Line Items]
Securities excluded from computation of diluted net loss per share	9.3	8.2

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Paragraph 1
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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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