Cost of purchased capped call options.

No definition available.

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- Definition

Debt instrument modification expense recognized.

+ References

No definition available.

+ Details

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- Definition

Proceeds from capped call options.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The month and year (YYYY-MM) the financial instrument was issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

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- Details

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Basic and Diluted Net Loss per Share - Additional Information (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended			3 Months Ended	6 Months Ended
	Mar. 31, 2021	Dec. 31, 2019	Nov. 30, 2017	Mar. 31, 2021	Jun. 30, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Amount of common stock reserved					5.9
0% Convertible Senior Notes Due 2026
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Payments to enter capped call options	$ 35.1				$ 35.1
Convertible debt Instrument, Issuance date, month and year	2021-03
0.125% Convertible Senior Notes Due 2024
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Payments to enter capped call options		$ 44.9			44.9
Convertible debt Instrument, Issuance date, month and year		2019-12
1.50% Convertible Senior Notes Due 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Payments to enter capped call options			$ 12.9
Convertible debt Instrument, Issuance date, month and year			2017-11
Proceeds from capped call options	$ 10.6	$ 5.8
Modification expense recognized				$ 0.2	$ 0.2